Dell Dimension 4400 "microprocessor has failed a bios test"

If Dells Website says to reseat the processor, why don't you do it?

... if it's more convenient -- and IF the system will boot to that point, you could try (a) running MemTest-86 for a while (www.memtest86.com) to check the memory  and/or  (b)  plugging in a different power supply (if you happen to have a Dell-compatible unit handy)  before you tackle removing the CPU & reseating, cleaning, applying thermal paste, etc.   (but odds are pretty good you have a CPU problem)

There should be more of an error report than that.
Can you get to BIOS?  How many beeps do you hear before this code comes up?

What is the specific pattern of beeps?  [Example: 3-short, 2-long, 1-shot, and so on]

CMOS batttery, cpu is not tight [lock is wrong or, not engaged, pin is bent, etc.]
If Dell says to reseat cpu, then they bought their own responsibility on warranty troubleshooting, that is, if they told you to do it, you cannot thereby void the warranty]

Sometimes chips need a slight push, such as the ROM chips, from time to time, to ensure contact to chip legs.  But not the cpu, as it's socket has horizontal clamping, but the normal ROM's on the motherboard sitting inside of sockets, 40/60 pin, etc., need a firm thumb push from time to time - with the board turned off!  Of course!

I am really just suggesting, while I'm playig with lynx browser a bit and considering going back to DOS web browser for EE.

:)

UPDATE:  After looking at Dell's website more carefully, it says that when the Diagnostic lights are Yellow, Yellow, Green, Yellow that you should contact technical support.  Machine is no longer under warantee.  

Also, there are no beeps when the system boots.  It's not even getting far enough to load the BIOS.  

Well, as I said in the first post, "... -- either the CPU is bad, is poorly seated, is getting indequate power, or you have a memory issue that's causing this symptom."

First thing you should do is see if you get to the BIOS with absolutely everything disconnected (hard drive, CD/DVD drive, floppy drive, etc.  EXCEPT one stick of memory.  If you do -- report back here and we'll continue the troubleshooting.

If not, and if you want to fix this yourself, you have to have some parts:  power supply  would be the 1st thing I'd try.

This is a good unit for your 4400:  http://www.pcpowercooling.com/products/viewproduct.php?show=T425D

3 yellows and 1 green; sounds like power supply if there isn't at least one beep.

Do you hear a relay click?  That would be the one inside of the power supply saying "I'm not turning on anymore."

:)

do they still use reed relays?

The FIX: got documentation from Dell and reseated the heatsink and processor.  So far, it works okay.

If no one has an objection, I'm going to have the question closed.

Craig

From my first post:   "...either the CPU is bad, is poorly seated, is ..."

Seems like that's exactly what you did :)

I don't really care what you do -- but it would be best if you tried your own remedies before posting a question and wasting the time of others to respond.

:)

nicely put

Sorry to hear that Dell is going secret on the beep codes though

Okay -- I'm going to divide the points.  I hope this makes everyone happy.