Raspberry Pi Forums

I tried 3 different power cables all microusb and 700ma at 5v bt none of them work! ;(

All costing 4.99!!!

Can anyone give me a link to amazon with one that will work!

What do you mean they don't work?  What happens to the display?  What lights come on?  Are you sure your SD card isn't the issue?

I've noticed that if my SD card isn't plugged in, or if the image isn't correct, the red power led comes on but nothing else happens.

Can you be more specific about would not work?  Were these random power supplies lying around?  Do you have a cell phone or other device that you can plug them into to see if they work there.  Sounds unlikely that all three would be bad, unless you have plugged all three into the same device that killed them.  Did you try a different outlet or extension cord, or did you plug them all in to the same wall outlet?

If you have, or can borrow a multimeter (the cheapest ones cost about the same as your power supply) you can tell for sure if it's  a power supply issue. Measure DC voltage between TP1 and TP2. It should be close to 5.0 V and solid. If it's below 4.75 V, and/or fluctuating, then the power supply and/or cable is inadequate.

Heres exactly what happens:

I verify image: correct

Then i put the sd card in

I plug all the other crap in

Then finally i put the cable in and....

Black screen nothing happens

Yes the power is on

These are the leds that are on : power

ADAMPOKE111 said:


Heres exactly what happens:

I verify image: correct

Then i put the sd card in

I plug all the other crap in

Then finally i put the cable in and....

Black screen nothing happens

Yes the power is on

These are the leds that are on : power


OK.  If the power LED (red) is coming on, that sounds like the power supplies are working to some degree.  My gut feeling is it's your SD card.  Is it inserted properly (this caught me out for about 10 min once - wasn't all the way in)?  What SD card is it and what Class?  If you unplug everything and just leave the card & power plugged in do you get the green OK light?

Are you using the HDMI or RCA connector?  If you are using HDMI you might not have the connector pushed fully in, it only has to be slightly out and you'll get nothing but a blank screen.

If the yellow LED doesn't flash then as has been mentioned your SD card might not be being accessed.

I tried what all you guys said and.... No. Something is definately wrong...

Do yu know any power cables that"ll definately work!?

Every power cable I've tried works:

Samsung Galaxy S charger - 700mA

HTC Mobile Charger - 1A

Kindle Charger - 1A

Kindle USB cable - straight to laptop USB

They all seem fine.

What is the make of your SD card and what is the Class?

What voltage do you get at the output of the power supply when not attached?

What amperage is the power supply?

With the power supply attached what reading do you get across TP1,2?

Have you tried a different manufacturers SD card?

ADAMPOKE111 said:


Do yu know any power cables that"ll definately work!?


There must be hundreds if not thousands of manufacturers worldwide that make power cables so giving you a specific one is going to be a bit random for you to find - if you're getting the red power led on then power is getting through and you should pay more attention to the next stage where the SD card is accessed - with an indication on the yellow led. What make & type of card are you using?

Heres where I stray form the subject a little...

My hard drive does not have enough memory to hold the Debian image WinDD and the Checksum program so.... I save everything to my FAT32 SanDisk 16GB RAW USB Pen Drive. Could the file encoder or decoder be the wrong one or is it the fact that I format it under a FAT32 system? Basically what I want to know is is my USB Drive gue problem?

ADAMPOKE111 said:


Heres where I stray form the subject a little...

My hard drive does not have enough memory to hold the Debian image WinDD and the Checksum program so.... I save everything to my FAT32 SanDisk 16GB RAW USB Pen Drive. Could the file encoder or decoder be the wrong one or is it the fact that I format it under a FAT32 system? Basically what I want to know is is my USB Drive gue problem?



Possibly, although I would be more concerned with the amount of general available space on your PC?  What OS are you running?  If you're concerned about this you could maybe shuffle things around so that the Debian image is on your OS drive.

Again, what is the make and Class of the SD card you're writing to - this could be very relevant.

There is some useful information in the wiki on this subject

http://elinux.org/R-Pi_Trouble.....on_display

http://elinux.org/R-Pi_Trouble.....mory_Cards

You do not say which operating system you used to create the SD card. If you are using Windows, writing to the card may fail if the card has not been completely erased beforehand.

With the power-led being ON, the power seems to be OK.

What happens if you put your finger over the powerled (it's kind of bright) and watch the OK led carefully?

There should be a very short green flash if it can't find the proper stuff on the SD card. But the flash means that the stuff is up-and-running.

I'd still bet on that you are having trouble getting a proper SD card.

How about the following: Pop the SD card in a windows PC and report what files you see.