ajaic
Posts: 2
Joined: Sat Feb 06, 2016 7:11 pm

Re: Overclocking

Sat Feb 06, 2016 7:20 pm

I bought a raspberry pi b+ off a seller on ebay who claimed 1300mhz stable. And I can't complain it works lovely and I got it stable up to 1420mhz. But as soon as I raise the core clock above default I am plagued with SD card corruption. I thought there was a firmware update a while back that fixed that issue? Does anyone have suggestions?

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GTR2Fan
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Location: South East UK

Re: Overclocking

Sat Feb 06, 2016 10:12 pm

ajaic wrote:I bought a raspberry pi b+ off a seller on ebay who claimed 1300mhz stable. And I can't complain it works lovely and I got it stable up to 1420mhz.
I very much doubt that it's stable at 1.3GHz, let alone 1.42, unless he's hardware-modded the Pi to give the CPU a crazily high voltage to run from. You need to extensively stress test to be sure that an overclock is entirely stable.
But as soon as I raise the core clock above default I am plagued with SD card corruption. I thought there was a firmware update a while back that fixed that issue? Does anyone have suggestions?
Yes. Start off with the standard recommended 1000/500/500 overclock and work your way up from there slowly, stress testing every step of the way. Attempting to troubleshoot with the current clock speeds will be much harder than starting over from scratch.

Tip: Always take other people's overclocking claims with a very large bucket of salt unless they're prepared to provide evidence of successful stress testing. ;)
Pi2B Mini-PC/Media Centre: ARM=1GHz (+3), Core=500MHz, v3d=500MHz, h264=333MHz, RAM=DDR2-1200 (+6/+4/+4+schmoo). Sandisk Ultra HC-I 32GB microSD card on '50=100' OCed slot (42MB/s read) running Raspbian/KODI16, Seagate 3.5" 1.5TB HDD mass storage.

ajaic
Posts: 2
Joined: Sat Feb 06, 2016 7:11 pm

Re: Overclocking

Sun Feb 07, 2016 7:06 pm

@GTR2Fan the board has been modified to supply a higher voltage to the cpu. And I know running it outside of spec is bound to cause problems. But as far as I can tell the guy did a good job at testing the board as I have quite a detailed report about what the board is capable of. It is only the core clock that causes me problems when I change it, so before assuming it is the voltage mod causing problems I'd like to explore other possible causes.

I will try what you suggested. Set the settings to 1000/500/500 and see what I can learn. Is there a chance that a specific chip just can't run its core clock outside of its default setting?

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GTR2Fan
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Location: South East UK

Re: Overclocking

Sun Feb 07, 2016 7:35 pm

ajaic wrote:Is there a chance that a specific chip just can't run its core clock outside of its default setting?
Assuming that the ARM voltage had been artificially cranked up (which it turns out it has), I was wondering the same thing. Yes. It's highly possible. Are you able to lower the ARM/GPU Core voltage down to normal levels by using negative numbers for over_voltage just to see if it helps? Values down to -16 are valid.

An unmodified Pi B+ or 2B is usually 100% stable at 1GHz ARM and 500MHz Core at an unmodified over_voltage=3 if that's any help as a reference. A change of 1 normally gives a voltage change of 25mV, but I'm not sure if that still holds true on a modded board.
Pi2B Mini-PC/Media Centre: ARM=1GHz (+3), Core=500MHz, v3d=500MHz, h264=333MHz, RAM=DDR2-1200 (+6/+4/+4+schmoo). Sandisk Ultra HC-I 32GB microSD card on '50=100' OCed slot (42MB/s read) running Raspbian/KODI16, Seagate 3.5" 1.5TB HDD mass storage.

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sat Feb 27, 2016 2:45 pm

Hi All,

New member, but been reading and following this thread for a while. Awesome work on the OC front. I run a few RPi2 using Openelec running a Dev version of Jarvis. I have managed to get my Sdram running at 550, but struggling to get any higher. This is where I'm stuck. I don't actually know what firmware I'm using and if it's the latest? How would I find this out on openelec? you can't update with rpi-update as openelec isn't a writable system. Any pointers as to finding out? I updated yesterday via adding the System System.md5, Kernel and Kernel.md5 to my update folder. The Dev update was released yesterday so I figure I may be on the latest build? Not sure I could of got 550 on the sdram if I wasn't?

I still can't get Hevec x265 files to play though, they are juddery and laggy. I was lead to believe this is fixed in the latest firmware? So can you guys help? ties in to what I'm trying to achieve with my Overclocking. Where and how can I tell what my firmware ver is? and where and how can I get the latest and update?

Many thanks, I now I've asked a lot, I hope it is clear and not too much trouble :) Cheers

milhouse
Posts: 641
Joined: Mon Jan 16, 2012 12:59 pm

Re: Overclocking

Sat Feb 27, 2016 3:11 pm

TheEgo wrote:Hi All,

New member, but been reading and following this thread for a while. Awesome work on the OC front. I run a few RPi2 using Openelec running a Dev version of Jarvis. I have managed to get my Sdram running at 550, but struggling to get any higher. This is where I'm stuck. I don't actually know what firmware I'm using and if it's the latest? How would I find this out on openelec? you can't update with rpi-update as openelec isn't a writable system. Any pointers as to finding out? I updated yesterday via adding the System System.md5, Kernel and Kernel.md5 to my update folder. The Dev update was released yesterday so I figure I may be on the latest build? Not sure I could of got 550 on the sdram if I wasn't?

I still can't get Hevec x265 files to play though, they are juddery and laggy. I was lead to believe this is fixed in the latest firmware? So can you guys help? ties in to what I'm trying to achieve with my Overclocking. Where and how can I tell what my firmware ver is? and where and how can I get the latest and update?

Many thanks, I now I've asked a lot, I hope it is clear and not too much trouble :) Cheers
"vcgencmd version" will tell you your firmware version.

"lsb_release" will tell you your OpenELEC version. If it's an official release (6.0.1) then it's not going to have the latest firmware with schmoo support.

If you want the latest, bleeding edge, nightly builds of OpenELEC with very latest firmware: http://forum.kodi.tv/showthread.php?tid=250817

dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
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Location: Cambridge

Re: Overclocking

Sat Feb 27, 2016 3:53 pm

TheEgo wrote:.
I still can't get Hevec x265 files to play though, they are juddery and laggy. I was lead to believe this is fixed in the latest firmware? So can you guys help? ties in to what I'm trying to achieve with my Overclocking. Where and how can I tell what my firmware ver is? and where and how can I get the latest and update?
No. The optimisations are in ffmpeg/kodi. OE 6 doesn't include HEVC acceleration. There will be some HEVC acceleration in OE 7 (not released yet).
The bleeding edge Milhouse builds have the best performance for HEVC (which will be improved further if you overclock, including sdram overclock).

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sat Feb 27, 2016 4:07 pm

Cheers Millhouse for the fast reply.

I know what version of Openelec I have, I updated yesterday (it was posted to http://openelec.thestateofme.com/dev_builds/ ) it's the last build posted on 26th Feb. I hope it's ok to link to this.

I'll look now for my version. I'm happy with the build I have, I've tried your builds via the openelec dev tool and I find them too unstable for my device (I say that as it's probably my end) plus they run Krypton after 1204 don't they? Is there a way to just get the firmware without the actual version? or is that a ridiculous thing to say? I know how to add the 4 files system,system.md5, kernel and kernel.md5 to the update folder, but unclear if this updates the firmware or just the build type (or both)

What if I add the start.elf and fixup.dat to the SD card? will this just update the firmware? I have been told this is the latest firmware from this link https://github.com/raspberrypi/firmware ... aster/boot I have the two files from there, but with the X in the name as that is what I was told. I figured I'd come here as I'm going into this with only some knowledge, so wish to expand that. Will doing what I've just said give me a newer firmware?

I'm running Kodi 16 Git:a5f3a99 (i know that's a ref for Github) Revision says 2a01041. Where do I add 'vcgencmd version' to get the firmware?

Again so sorry for all the questions, it's not without hours and hours of trying to figure this out myself by trial and error and reading articles and forums.

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sat Feb 27, 2016 4:14 pm

dom wrote:
TheEgo wrote:.
I still can't get Hevec x265 files to play though, they are juddery and laggy. I was lead to believe this is fixed in the latest firmware? So can you guys help? ties in to what I'm trying to achieve with my Overclocking. Where and how can I tell what my firmware ver is? and where and how can I get the latest and update?
No. The optimisations are in ffmpeg/kodi. OE 6 doesn't include HEVC acceleration. There will be some HEVC acceleration in OE 7 (not released yet).
The bleeding edge Milhouse builds have the best performance for HEVC (which will be improved further if you overclock, including sdram overclock).
Take a look at my last post for a little more info on version I'm running. It's a dev one (from the link included) so Kodi 16 and I have Sdram working at 550mhz and stable. Just trying to establish if I'm on the best and most stable build to get HEVEC to play (which clearly i'm not) and will a firmware upgrade do the job like I've been told or do I need to upgrade to a different version and lose stability? I don't have any support for Kodi 17 with my skin. I've tried the Millhouse latest version and just won't work with my RP2 and the Titan skin I have. Do I need to accept confluence skin if I'm to get HEVEC performance? all other file types play like a dream and my system is slick and fast with a mSata SSD running the system.

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sat Feb 27, 2016 4:16 pm

My config.txt file for your info :)

gpu_mem=280

arm_freq=1064
core_freq=560
gpu_freq=400
over_voltage=6
over_voltage_sdram=3

sdram_freq=550
sdram_schmoo=0x02000020
over_voltage_sdram_p=4
over_voltage_sdram_i=2
over_voltage_sdram_c=2

disable_pvt=1
avoid_pwm_pll=1

v3d_freq=350
h264_freq=350
isp_freq=350

force_turbo=1
disable_splash=1
max_usb_current=1
temp_limit=85

dtoverlay=sdhost,overclock_50=100

milhouse
Posts: 641
Joined: Mon Jan 16, 2012 12:59 pm

Re: Overclocking

Sat Feb 27, 2016 4:33 pm

TheEgo wrote:Cheers Millhouse for the fast reply.

I know what version of Openelec I have, I updated yesterday (it was posted to http://openelec.thestateofme.com/dev_builds/ ) it's the last build posted on 26th Feb. I hope it's ok to link to this.

I'll look now for my version. I'm happy with the build I have, I've tried your builds via the openelec dev tool and I find them too unstable for my device (I say that as it's probably my end) plus they run Krypton after 1204 don't they? Is there a way to just get the firmware without the actual version? or is that a ridiculous thing to say? I know how to add the 4 files system,system.md5, kernel and kernel.md5 to the update folder, but unclear if this updates the firmware or just the build type (or both)

What if I add the start.elf and fixup.dat to the SD card? will this just update the firmware? I have been told this is the latest firmware from this link https://github.com/raspberrypi/firmware ... aster/boot I have the two files from there, but with the X in the name as that is what I was told. I figured I'd come here as I'm going into this with only some knowledge, so wish to expand that. Will doing what I've just said give me a newer firmware?
I'm not sure I understand what you're trying to ask or achieve - combining OpenELEC kernel.img+SYSTEM with different older or newer firmware is likely to result in issues that nobody else is able to replicate so not something I'd advise.

As dom explained, the HEVC optimisations are in ffmpeg/Kodi which is in the SYSTEM file, so you'll need to switch to one of my Kodi 17 builds to get the latest HEVC optimisations.

Yes, #1204 is the last Jarvis build, it's all Krypton thereafter. Stability should be no worse than Jarvis, while performance should be improved - if you're experiencing instability then report it in the Kodi Forum test thread.
TheEgo wrote: I'm running Kodi 16 Git:a5f3a99 (i know that's a ref for Github) Revision says 2a01041. Where do I add 'vcgencmd version' to get the firmware?
You run "vcgencmd version" in ssh.

milhouse
Posts: 641
Joined: Mon Jan 16, 2012 12:59 pm

Re: Overclocking

Sat Feb 27, 2016 4:39 pm

TheEgo wrote:
dom wrote:
TheEgo wrote:.
Do I need to accept confluence skin if I'm to get HEVEC performance? all other file types play like a dream and my system is slick and fast with a mSata SSD running the system.
Pretty much, yes. Third party skins are playing catchup as Kodi 17 has (intentionally) broken compatibility with Kodi 16 skins - any instability is therefore due to your incompatible skins. Some third-party skins such as Aeon Nox 5 (available from github) have added Kodi 17 support, no idea about Titan.

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GTR2Fan
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Location: South East UK

Re: Overclocking

Sat Feb 27, 2016 4:45 pm

@TheEgo: The instability you're suffering with some versions may be down to a marginally stable overclock. Simply being able to run a particular version of a particular media centre app without crashes is no proof of stability.

Unless you've actually stress-tested the overclock thoroughly or tried the seemingly unstable versions with no overclock, that leaves a very large unknown that simply can't be ignored.
Pi2B Mini-PC/Media Centre: ARM=1GHz (+3), Core=500MHz, v3d=500MHz, h264=333MHz, RAM=DDR2-1200 (+6/+4/+4+schmoo). Sandisk Ultra HC-I 32GB microSD card on '50=100' OCed slot (42MB/s read) running Raspbian/KODI16, Seagate 3.5" 1.5TB HDD mass storage.

JimmyN
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Location: Virginia, USA

Re: Overclocking

Sat Feb 27, 2016 4:49 pm

TheEgo wrote:I have managed to get my Sdram running at 550, but struggling to get any higher.
550 is way too high. The Micron RAM module, on mine at least, is specified as 400mHz, and since the timings are fixed and can't be changed pushing it much above 480 causes instability, though increasing sdram voltage may help. But you won't get much, if any, performance improvements by overvolting the RAM and pushing it above 480 anyway, maybe 1% or so at best. The biggest performance boost will come from increasing the L2 cache (core_freq) speed.

The default overclock for the RPi2 in raspi-config are not the best settings, and may not even be stable on some boards. It sets the SDRAM at 500 which is too high, and the L2 cache at only 250 which is way too low. You need to increase the L2 cache to 500, if you're using an arm_freq of 1000, or 550 if you're using an arm_freq of 1100. Due to their interaction, for best stability try to keep a 2:1 ratio between arm_freq and core_freq.

If you use a arm_freq of 1000, a core_freq of 500, and a sdram_freq of 480 it should be stable without any overvolting, including no need to overvolt the sdram, and still see quite a performance increase. Then you can move up from there to see what that specific board can handle.

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sat Feb 27, 2016 5:06 pm

milhouse wrote:
TheEgo wrote:Cheers Millhouse for the fast reply.

I know what version of Openelec I have, I updated yesterday (it was posted to http://openelec.thestateofme.com/dev_builds/ ) it's the last build posted on 26th Feb. I hope it's ok to link to this.

I'll look now for my version. I'm happy with the build I have, I've tried your builds via the openelec dev tool and I find them too unstable for my device (I say that as it's probably my end) plus they run Krypton after 1204 don't they? Is there a way to just get the firmware without the actual version? or is that a ridiculous thing to say? I know how to add the 4 files system,system.md5, kernel and kernel.md5 to the update folder, but unclear if this updates the firmware or just the build type (or both)

What if I add the start.elf and fixup.dat to the SD card? will this just update the firmware? I have been told this is the latest firmware from this link https://github.com/raspberrypi/firmware ... aster/boot I have the two files from there, but with the X in the name as that is what I was told. I figured I'd come here as I'm going into this with only some knowledge, so wish to expand that. Will doing what I've just said give me a newer firmware?
I'm not sure I understand what you're trying to ask or achieve - combining OpenELEC kernel.img+SYSTEM with different older or newer firmware is likely to result in issues that nobody else is able to replicate so not something I'd advise.

As dom explained, the HEVC optimisations are in ffmpeg/Kodi which is in the SYSTEM file, so you'll need to switch to one of my Kodi 17 builds to get the latest HEVC optimisations.

Yes, #1204 is the last Jarvis build, it's all Krypton thereafter. Stability should be no worse than Jarvis, while performance should be improved - if you're experiencing instability then report it in the Kodi Forum test thread.
TheEgo wrote: I'm running Kodi 16 Git:a5f3a99 (i know that's a ref for Github) Revision says 2a01041. Where do I add 'vcgencmd version' to get the firmware?
You run "vcgencmd version" in ssh.
You pretty much covered it all with this. I was advised to update the start.elf and the fixup.dat to get the latest firmware which would help with my HEVEC problem. It appears that isn't going to work, so thanks for clearing it up. The guy who told me is pretty knowledgeable, but I'd rather learn and make educated changes. I think my firmware must be pretty new given I can even run the Sdram at 550. As for instabilities I refer mainly to Skins (which you've covered) and not with performance, or freezing etc so I don't think it is my settings.

I think I'll go with a seperate build on a 32gb SD card and use your upto date builds and try and get my hands on the skin you refer too. Titan have a Beta that will be out in days. So I'll have my main system and then a test system to run your builds and check out the HEVEC capabilties. I was just led to beleive I could do it on Jarvis with a firmware update as the chap insists he has it on his system.

Thanks for the clarity. I'll go ahead and test your daily builds. Cheers and thanks Dom for also lending a hand and explaining it all a little better. Much appreciated. I'll stick around and go through the forum and learn as much as I can.

Re my config file and settings. It's working fine on hours and hours of video playback and navigation. I'm happy that it's 'stable' but how do you test? via ssh? what is the software and/or process that you guys refer to? I'd be intrigued to do a more formal test.

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GTR2Fan
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Location: South East UK

Re: Overclocking

Sat Feb 27, 2016 5:08 pm

JimmyN wrote:550 is way too high. The Micron RAM module, on mine at least, is specified as 400mHz, and since the timings are fixed and can't be changed pushing it much above 480 causes instability, though increasing sdram voltage may help. But you won't get much, if any, performance improvements by overvolting the RAM and pushing it above 480 anyway, maybe 1% or so at best.
Read the past couple of pages of this thread, Jimmy. Almost any Pi2B RAM will be completely stable at 500MHz with some achieving complete stability at 600MHz with the appropriate updates and config.txt settings.

Also, are you sure that L2 cache performance is still tied to the Core clock frequency when the BCM2836 on a Pi2B has its own integrated 512KB L2 cache? I can't say that I've been bothered to measure it myself.
Pi2B Mini-PC/Media Centre: ARM=1GHz (+3), Core=500MHz, v3d=500MHz, h264=333MHz, RAM=DDR2-1200 (+6/+4/+4+schmoo). Sandisk Ultra HC-I 32GB microSD card on '50=100' OCed slot (42MB/s read) running Raspbian/KODI16, Seagate 3.5" 1.5TB HDD mass storage.

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GTR2Fan
Posts: 1601
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Location: South East UK

Re: Overclocking

Sat Feb 27, 2016 5:21 pm

TheEgo wrote:I'm happy that it's 'stable' but how do you test? via ssh? what is the software and/or process that you guys refer to? I'd be intrigued to do a more formal test.
Many of the 'formal' tests I've tried don't seem to stress test anything particularly thoroughly, but running memtester from a terminal will tell you whether your RAM is stable or not by typing...

Code: Select all

memtester 700 10
... into a terminal. If it can survive all 10 passes without errors then you can be reasonably certain that it's completely stable.

As for stressing the CPUs and GPU and Core, very little beats Quake 3 Arena that I can find. There's a guide on this forum to installing the shareware version. The search box should find it for you. 30 minutes of that seems to prove beyond any reasonable doubt that the GPU and Core are stable as it often crashes in just the first few minutes if it isn't. It also seems to be reasonably conclusive proof of CPU stability too.

Your overclock may turn out to be perfectly stable as it is, but it pays to check it out or it can seemingly randomly sneak up and bite you on the backside further down the line leaving you scratching your head as to why new software packages you install behave oddly or crash.
Pi2B Mini-PC/Media Centre: ARM=1GHz (+3), Core=500MHz, v3d=500MHz, h264=333MHz, RAM=DDR2-1200 (+6/+4/+4+schmoo). Sandisk Ultra HC-I 32GB microSD card on '50=100' OCed slot (42MB/s read) running Raspbian/KODI16, Seagate 3.5" 1.5TB HDD mass storage.

jahboater
Posts: 4846
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Re: Overclocking

Sat Feb 27, 2016 5:30 pm

Read the past couple of pages of this thread, Jimmy. Almost any Pi2B RAM will be completely stable at 500MHz with some achieving complete stability at 600MHz with the appropriate updates and config.txt settings.
Definitely. See the changes to the firmware by dom, some time ago in this thread which I presume are included with Rasbian 02-09. The standard Pi2 overclock in raspi-config is now "modest".

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sat Feb 27, 2016 7:18 pm

GTR2Fan wrote:
TheEgo wrote:I'm happy that it's 'stable' but how do you test? via ssh? what is the software and/or process that you guys refer to? I'd be intrigued to do a more formal test.
Many of the 'formal' tests I've tried don't seem to stress test anything particularly thoroughly, but running memtester from a terminal will tell you whether your RAM is stable or not by typing...

Code: Select all

memtester 700 10
... into a terminal. If it can survive all 10 passes without errors then you can be reasonably certain that it's completely stable.

As for stressing the CPUs and GPU and Core, very little beats Quake 3 Arena that I can find. There's a guide on this forum to installing the shareware version. The search box should find it for you. 30 minutes of that seems to prove beyond any reasonable doubt that the GPU and Core are stable as it often crashes in just the first few minutes if it isn't. It also seems to be reasonably conclusive proof of CPU stability too.

Your overclock may turn out to be perfectly stable as it is, but it pays to check it out or it can seemingly randomly sneak up and bite you on the backside further down the line leaving you scratching your head as to why new software packages you install behave oddly or crash.
Cheers for that, I'll give it a go. I'm also trying Millhouse latest build on a different SD card/setup, so I'll see how my settings fair on that. Found a skin that works for it too, so may well be updating daily from now on haha!!

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sat Feb 27, 2016 7:20 pm

JimmyN wrote:
TheEgo wrote:I have managed to get my Sdram running at 550, but struggling to get any higher.
550 is way too high. The Micron RAM module, on mine at least, is specified as 400mHz, and since the timings are fixed and can't be changed pushing it much above 480 causes instability, though increasing sdram voltage may help. But you won't get much, if any, performance improvements by overvolting the RAM and pushing it above 480 anyway, maybe 1% or so at best. The biggest performance boost will come from increasing the L2 cache (core_freq) speed.

The default overclock for the RPi2 in raspi-config are not the best settings, and may not even be stable on some boards. It sets the SDRAM at 500 which is too high, and the L2 cache at only 250 which is way too low. You need to increase the L2 cache to 500, if you're using an arm_freq of 1000, or 550 if you're using an arm_freq of 1100. Due to their interaction, for best stability try to keep a 2:1 ratio between arm_freq and core_freq.

If you use a arm_freq of 1000, a core_freq of 500, and a sdram_freq of 480 it should be stable without any overvolting, including no need to overvolt the sdram, and still see quite a performance increase. Then you can move up from there to see what that specific board can handle.
Cheers for the advice. I can assure you of read loads on overclocking the sdram and many are able to get 550 or even higher with new versions of Openelec and new firmware. I've been running it for a while now at that setting and watched live football, videos, installed many things etc! all without a single freeze, hang, anything.

Cheers for the reply though

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sun Feb 28, 2016 12:00 pm

[/quote]

You run "vcgencmd version" in ssh.[/quote]

Hi back with another question. Can you think of a reason I can't access the ssh in putty? I get a fatal error Network error: Connection refused. The only thing I can think it can be is I installed a mSata SSD card the other day and reloaded my system so that it runs off the SSD as opposed to the HDD I was using. I've run the HDD/SD card setup for over 18 months and could always access SSH via putty, so this is the only change. I restored from a backup, so all settings are the same. SSH is enabled etc, IP address is correct. Could the SSD be blocking the connection? I'm at a loss. There isn't anything in the config file (back to overclocking) that would stop access to ssh is there?

Pulling my hair out as I can't check the firmware version. Totally fine on my other two Pi's running with HDD's with the same build and backup....

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sun Feb 28, 2016 12:21 pm

TheEgo wrote:
GTR2Fan wrote:
TheEgo wrote:I'm happy that it's 'stable' but how do you test? via ssh? what is the software and/or process that you guys refer to? I'd be intrigued to do a more formal test.
Many of the 'formal' tests I've tried don't seem to stress test anything particularly thoroughly, but running memtester from a terminal will tell you whether your RAM is stable or not by typing...

Code: Select all

memtester 700 10
... into a terminal. If it can survive all 10 passes without errors then you can be reasonably certain that it's completely stable.

As for stressing the CPUs and GPU and Core, very little beats Quake 3 Arena that I can find. There's a guide on this forum to installing the shareware version. The search box should find it for you. 30 minutes of that seems to prove beyond any reasonable doubt that the GPU and Core are stable as it often crashes in just the first few minutes if it isn't. It also seems to be reasonably conclusive proof of CPU stability too.

Your overclock may turn out to be perfectly stable as it is, but it pays to check it out or it can seemingly randomly sneak up and bite you on the backside further down the line leaving you scratching your head as to why new software packages you install behave oddly or crash.
Hi mate, how do I run/install memtest on an openelec system? what OS are you using? If I type in Memtest as you described into putty via ssh it says it doesn't exist, (I'm guessing this is because it isn't installed? So how do I install?) Are you guys (Millhouse? using openlec? do you have a linux system on your pc? is that the difference?)

I'm so confused as to how to stress test my system and config by these means. Any further help would be greatly appreciated. Thank you.

milhouse
Posts: 641
Joined: Mon Jan 16, 2012 12:59 pm

Re: Overclocking

Sun Feb 28, 2016 12:49 pm

TheEgo wrote: Hi mate, how do I run/install memtest on an openelec system? what OS are you using? If I type in Memtest as you described into putty via ssh it says it doesn't exist, (I'm guessing this is because it isn't installed? So how do I install?) Are you guys (Millhouse? using openlec? do you have a linux system on your pc? is that the difference?)

I'm so confused as to how to stress test my system and config by these means. Any further help would be greatly appreciated. Thank you.
To install memtester in OpenELEC:

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wget http://nmacleod.com/public/oebuild/memtester -O ~/memtester && chmod +x ~/memtester
To run the test, configure your gpu_mem to 64MB ("gpu_mem=64" in config.txt, so that more RAM can be tested), shut down kodi ("systemctl stop kodi" to release as much RAM as possible), then run "memtester 850 10". If it passes 10 times without fail, you should be good - running a 1080 HEVC movie will then be a good test of both RAM and CPU.
Last edited by milhouse on Sun Feb 28, 2016 12:50 pm, edited 1 time in total.

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GTR2Fan
Posts: 1601
Joined: Sun Feb 23, 2014 9:20 pm
Location: South East UK

Re: Overclocking

Sun Feb 28, 2016 12:49 pm

TheEgo wrote:Hi mate, how do I run/install memtest on an openelec system? what OS are you using? If I type in Memtest as you described into putty via ssh it says it doesn't exist, (I'm guessing this is because it isn't installed? So how do I install?) Are you guys (Millhouse? using openlec? do you have a linux system on your pc? is that the difference?)
Hi. I'm running a full Raspbian Jessie install but can't remember whether or not memtester is a pre-installed package or not. You can add it with...

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sudo apt-get install memtester
Running it with...

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memtester 700 10
...sends it around 10 loops of stress testing 700MB of RAM. Depending on your current GPU/CPU RAM split and whatever else is currently running, you may not have 700MB free to test, so if it complains, reduce this number until it stops complaining. Ideally, you need to test as much RAM as possible, so try for more than 700MB if you can.

There is also a CPU stress tester that's fairly conclusive proof called stress, but bear in mind that it doesn't raise the SOC temperature anywhere near as much as thrashing the GPU does, so it only really proves CPU stability at low temperatures. You can install that with...

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sudo apt-get install stress
...and run it with...

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stress --cpu 4 --timeout 900
...to stress all 4 cores of a Pi2B for 15 minutes.

Quake 3 Arena does an excellent job of testing GPU and system-wide workload stability once you're confident that the CPU and RAM seem to be stable in isolation largely due to the vastly increased running temperature it generates.

The overclock in my sig is a result of the above testing methodology. Each clock tested in isolation can go a little higher, but instability has always crept in somewhere with higher clocks. As is always the case with overclocking, YMMV.
Pi2B Mini-PC/Media Centre: ARM=1GHz (+3), Core=500MHz, v3d=500MHz, h264=333MHz, RAM=DDR2-1200 (+6/+4/+4+schmoo). Sandisk Ultra HC-I 32GB microSD card on '50=100' OCed slot (42MB/s read) running Raspbian/KODI16, Seagate 3.5" 1.5TB HDD mass storage.

TheEgo
Posts: 35
Joined: Sat Feb 27, 2016 2:37 pm

Re: Overclocking

Sun Feb 28, 2016 2:21 pm

milhouse wrote:
TheEgo wrote: Hi mate, how do I run/install memtest on an openelec system? what OS are you using? If I type in Memtest as you described into putty via ssh it says it doesn't exist, (I'm guessing this is because it isn't installed? So how do I install?) Are you guys (Millhouse? using openlec? do you have a linux system on your pc? is that the difference?)

I'm so confused as to how to stress test my system and config by these means. Any further help would be greatly appreciated. Thank you.
To install memtester in OpenELEC:

Code: Select all

wget http://nmacleod.com/public/oebuild/memtester -O ~/memtester && chmod +x ~/memtester
To run the test, configure your gpu_mem to 64MB ("gpu_mem=64" in config.txt, so that more RAM can be tested), shut down kodi ("systemctl stop kodi" to release as much RAM as possible), then run "memtester 850 10". If it passes 10 times without fail, you should be good - running a 1080 HEVC movie will then be a good test of both RAM and CPU.
Thank you :)

Any idea why my ssh access may be restricted? (it won't let me connect, as per previous post) Could it be the SSD and permissions? It's the only thing I can think of. I've checked all other Pi's on the exact same build (from the same backup) and they access it via putty just fine as they always have. Only difference is the SSD I installed on the one that won't access SSH. Cheers again.

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