The Raspberry Pi 400 thread!

[lb]

Uh, what's so hard to understand about the clock frequency thing?

The Raspberry Pi 4 is validated to work at 1.5 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.5 GHz.

The Raspberry Pi 400 is validted to work at 1.8 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.8 Ghz.

It's called binning and it's hardly new. Every chip manufacturer does it! [moderator, no its NOT just binning, the RPI 400 has a completely new SoC, with enhancements that make clocking it higher possible]

[Heater]

Wow! That is gorgeous.

As someone noted already it would be great to have that motherboard available on it's own. That form factor would be sweet in so many places .

Excellent job.

That's your POV, but what is the market for this nice little computer keyboard: Education as this was done in the 80's? Then, A POE switch feeding networking+power to the whole classroom would make sense. As well as an audio jack.

I find that a rather odd statement. Do they still have ethernet cables trailing around classrooms, let alone PoE cabability? I have hardly seen an ethernet cable anywhere in home or office for many years now. And none of them with PoE, unless it was something I rigged up myself.

Similarly for audio jacks.

So, what do you mean as "intended use"?

Intended use is clear to me. It's a year 2020 BBC Computer. It's a tiny computer for your desk.

[hippy]

I think you have got hold of entirely the wrong end of the stick here.

I had. Please accept my apologies.

[RaTTuS]

well I've gone an ordered one of these ....
I've also got to see about a CM4 option but I may go with a Christmas pressize for myself with that

[rpiMike]

I like the GPIO labelling:

[Selectortone]

Intended use? Take you pick. First time Pi users, people who need a cheap PC, commercial sites where twin monitor setup are used (e.g. call
centres, but clearly vast prospects elsewhere as well), education of course, third world. It's endless. Anywhere you need a cheap PC.

Of course, if it doesn't suit your use case, that's fine, use something else.

“You can please some of the people all of the time, you can please all of the people some of the time, but you can’t please all of the people all of the time.”

I think it's absolutely brilliant.

[jamesh]

Intended use? Take you pick. First time Pi users, people who need a cheap PC, commercial sites where twin monitor setup are used (e.g. call
centres, but clearly vast prospects elsewhere as well), education of course, third world. It's endless. Anywhere you need a cheap PC.

Of course, if it doesn't suit your use case, that's fine, use something else.

“You can please some of the people all of the time, you can please all of the people some of the time, but you can’t please all of the people all of the time.”

I think it's absolutely brilliant.

Excellent!

[davidcoton]

JamesH - what's the type code that is going to be used for this model (i.e. the one in the model's revision code)?

13, the docs have been updated.

The published (online) version isn't showing it yet. CM4 is there.
11 -- 4B
12 -- ??? 4A ??? (GD&R)
13 -- 400
14 -- CM4

[jamesh]

It's called binning and it's hardly new. Every chip manufacturer does it!

Actually, it's more of a better clock gating in the C0 chip means we can power down more parts of the chip not ins use, which means less heat, which means more ability for higher clocks, which is boosted when combined with the high capacity heat spreader in the Pi 400.

Not sure we do binning.

[fanoush]

constant Server Error messages due to too many people

If you see error 400 then it is the product announcement!

[jamesh]

JamesH - what's the type code that is going to be used for this model (i.e. the one in the model's revision code)?

13, the docs have been updated.

The published (online) version isn't showing it yet. CM4 is there.
11 -- 4B
12 -- ??? 4A ??? (GD&R)
13 -- 400
14 -- CM4

I wondered when people would notice the gap in the revision codes. The CM4 has been on there for a week...

Online page has now updated.

[cleverca22]

It's called binning and it's hardly new. Every chip manufacturer does it!

Actually, it's more of a better clock gating in the C0 chip means we can power down more parts of the chip not ins use, which means less heat, which means more ability for higher clocks, which is boosted when combined with the high capacity heat spreader in the Pi 400.

Not sure we do binning.

but which peripherals are even unused enough to reduce the heat generation when gated?
is it just things like DSI/CSI being turned off, since the pi400 lacks those connectors?
or is it features the public doesn't even know of, that you cant name?

JamesH - what's the type code that is going to be used for this model (i.e. the one in the model's revision code)?

13, the docs have been updated.

ah, i had seen 13 in a start4.elf a few months ago, but i didnt know what it was, never expected something like this

[fruitoftheloom]

Uh, what's so hard to understand about the clock frequency thing?

The Raspberry Pi 4 is validated to work at 1.5 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.5 GHz.

The Raspberry Pi 400 is validted to work at 1.8 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.8 Ghz.

It's called binning and it's hardly new. Every chip manufacturer does it!

That is totally wrong and poppycock, the difference in clock speed is down to the Heat Sink used in the 400

[GaryH1]

JamesH - what's the type code that is going to be used for this model (i.e. the one in the model's revision code)?

13, the docs have been updated.

Thanks James, we must have cross-posted as I had a look before the revision code info was updated!

[jdb]

Uh, what's so hard to understand about the clock frequency thing?

The Raspberry Pi 4 is validated to work at 1.5 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.5 GHz.

The Raspberry Pi 400 is validted to work at 1.8 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.8 Ghz.

It's called binning and it's hardly new. Every chip manufacturer does it!

That is totally wrong and poppycock, the difference in clock speed is down to the Heat Sink used in the 400

Really? News to me. Obviously nothing to do with the months-long requalification campaign that we did for the C0 step.

[cleverca22]

Uh, what's so hard to understand about the clock frequency thing?

The Raspberry Pi 4 is validated to work at 1.5 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.5 GHz.

The Raspberry Pi 400 is validted to work at 1.8 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.8 Ghz.

It's called binning and it's hardly new. Every chip manufacturer does it!

That is totally wrong and poppycock, the difference in clock speed is down to the Heat Sink used in the 400

It's called binning and it's hardly new. Every chip manufacturer does it!

Actually, it's more of a better clock gating in the C0 chip means we can power down more parts of the chip not ins use, which means less heat, which means more ability for higher clocks, which is boosted when combined with the high capacity heat spreader in the Pi 400.

Not sure we do binning.

its not the heatsink alone, but a revision of the chip that reduces the heat generation overall

[LimboMan]

That is an awesome design. Kudos to RPi!

I really like the GPIO pins on the back- seems perfect for plugging in a monitor like this: https://www.waveshare.com/product/displ ... for-pi.htm

Last year a guy modded the Pi keyboard and with a Pi Zero: https://howchoo.com/g/zgmzytq1mmy/raspb ... i-keyboard

I would like to build something like that too. Maybe a Pi Zero W version of the Pi 400 but that would be asking too much

[cleverca22]

That is an awesome design. Kudos to RPi!

I really like the GPIO pins on the back- seems perfect for plugging in a monitor like this: https://www.waveshare.com/product/displ ... for-pi.htm

Last year a guy modded the Pi keyboard and with a Pi Zero: https://howchoo.com/g/zgmzytq1mmy/raspb ... i-keyboard

I would like to build something like that too. Maybe a Pi Zero W version of the Pi 400 but that would be asking too much

yeah, with just a few 3d-printed parts, you could clip that screen onto the pi400, and it would basically become a laptop without a battery/mouse

[fruitoftheloom]

Uh, what's so hard to understand about the clock frequency thing?

The Raspberry Pi 4 is validated to work at 1.5 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.5 GHz.

The Raspberry Pi 400 is validted to work at 1.8 GHz. That is, the manufacturer tests the chips and guarantees that they work correctly up to 1.8 Ghz.

It's called binning and it's hardly new. Every chip manufacturer does it!

That is totally wrong and poppycock, the difference in clock speed is down to the Heat Sink used in the 400

Really? News to me. Obviously nothing to do with the months-long requalification campaign that we did for the C0 step.

OK not just the 400s heat sink but a combination of heat sink and changes to the SoC, but nothing to do with binning which was intimated, in the post above.

Good to know that improvements are happening, and look forward to the next surprise....

[Wrongway]

Does anyone know whats on the included micro SD card. Is it NOOBS, one of the three Raspberry Pi OS versions or is it a special thats been done for the Pi 400.

[jamesh]

but which peripherals are even unused enough to reduce the heat generation when gated?
is it just things like DSI/CSI being turned off, since the pi400 lacks those connectors?
or is it features the public doesn't even know of, that you cant name?

Remember this gating can turn on and off many times per second. So it's not a turn this block off because we are not using for 10s type of thing. You could turn something off for 10ms every 20 milliseconds and save 50% ! TBH, the savings are less than that, you might turn a block off for only 10% or less over its duty cycle, but that is still an appreciable saving.

Blocks like 3D, HVS, codecs could all be turned off for perhaps a few milliseconds every frame, and even sub parts of those blocks perhaps - I do not know the details.

[Technocolour]

This gives me Amiga vibes. Nice.

I'm guessing the lack of a headphone jack boils down to the need for a large customer base to have audio in.

Good job, to everyone that's been involved.

[bomblord]

The blog post he uses and bolds the words "Faster, cooler" Raspberry Pi 4.

Is this actually running faster than a stock Pi 4? And is cooler just describing it being neat/interesting as opposed to operating temperature?

Edit: I seen the discussion on this page now (only went through the first page and didn't see anyone talking about it)

[fruitoftheloom]

The blog post he uses and bolds the words "Faster, cooler" Raspberry Pi 4.

Is this actually running faster than a stock Pi 4? And is cooler just describing it being neat/interesting as opposed to operating temperature?

Edit: I seen the discussion on this page now (only went through the first page and didn't see anyone talking about it)

https://www.tomshardware.com/amp/news/r ... r-thermals

[jdb]

but which peripherals are even unused enough to reduce the heat generation when gated?
is it just things like DSI/CSI being turned off, since the pi400 lacks those connectors?
or is it features the public doesn't even know of, that you cant name?

Remember this gating can turn on and off many times per second. So it's not a turn this block off because we are not using for 10s type of thing. You could turn something off for 10ms every 20 milliseconds and save 50% ! TBH, the savings are less than that, you might turn a block off for only 10% or less over its duty cycle, but that is still an appreciable saving.

Blocks like 3D, HVS, codecs could all be turned off for perhaps a few milliseconds every frame, and even sub parts of those blocks perhaps - I do not know the details.

Clock gating in hardware operates at a much finer granularity than that. It's at the microarchitectural level, and operates on a cycle-to-cycle basis. Chip synthesis tools can recognise conditions where inputs to a logic block are static, and outputs don't change, and choose to combinatorially disconnect the clock at a high level in the hierarchy. This saves dynamic power while operating *as well as* idle power.