No POST - Dead MB? Dead CPU? *solved*

[AnitaPeterson]

Hi folks,

I came across this stripped system, and I cannot figure out what's wrong with it, in order to determine whether it's worth salvaging or I should just cannibalize wht's good, and discard the rest.

It's a motherboard, CPU, video card and DVD writer, inside a case with a PSU attached.

I often come across discarded machines which are quite functional, so I do not automatically assume that it's defective without trying it first.

I've established the following:

- The motherboard is an ASUS P5K SE. No VGA onboard.
- I am not sure what the processor is, but judging by the Intel model/serial on the CPU cooler, it should be a dual-core post-P4 CPU, circa late 2007 - early 2008.
- The video card is an Nvidia EVGA Geforce 8500 GT (PCI-E)

The system does not POST.

Here's what I do:

1. I connect the VGA to a monitor, attach a PS/2 keyboard, a USB mouse, and push the power button. There's nothing on the screen. I get a single long beep, followed by two short ones in succession; this three-beep signal repeats continuously.
According to the motherboard manual, this indicates RAM is not detected.

2. I unplug the power, and follow the manual instructions to clear CMOS.

3. I install a single 1GB DDR2 PC-4300 (Apacer) module in slot 1B (as per manual)

4. I reconnect the power cable, and push power. The fans start turning, the LED on the keyboard flash. Nothing else happens, screen stays black as if there's nothing connected to it. No beeps, either.

5. I disconnect the power once again and take out the video card.

6. Upon restart, no beeps (manual says there should be a succession of beeps indicating VGA not found).

7. I try a different video card. Same behaviour as described under 4.

Is there anything else I should try? Can the CPU be dead, or is the motherboard fried?

Please feel free to suggest remedial and/or verification procedures I haven't listed above.

I'm doing this as an exercise, for learning. If I can get the machine to run (I have lots of spare components!) I can give it away to a charity.

Thanks much in advance.


*edit* It now works! See my later post in the thread - the RAM I tried wasn't a good fit for this board.

 

[krnmastersgt]

Seems to me like the motherboard might be damaged as it can detect missing/faulty ram but is unable to discern that it has no video output. Doesn't really rule out the CPU however unless you have another board to test it in.

 

[AnitaPeterson]

Alas, I don't have another Intel 775 socket board...
Is there any procedure to test further?

 

[krnmastersgt]

Nothing comes to mind without other hardware to test it against, do both RAM modules check out OK with the motherboard?

 

[philipma1957]

try 1 stick in every slot. if no post try the next stick in every slot if no post you need more gear to test.

a slot (first) could be bad a stick could be bad.


my test will work if 1 stick and 1 slot work. and the problem was a stick or a slot issue.


it is free to try it.

 

[vailr]

Sorry, you need more spare components to compare: good vs. faulty.
More likely to less likely faulty component:
PSU
Memory
Motherboard
CPU

 

[SKORPI0]

is the 4-pin 12V CPU power socket plugged in?

 

[mfenn]

Do you know that the RAM you're testing with is functional?

Also, try using a known good PSU.

 

[BTRY B 529th FA BN]

if you have an analog voltage reader test out the PSU

 

[AnitaPeterson]

Thank you for the input so far, folks!

I'm going to try a couple of spare (known to be good) PSUs, as well as a few other RAM sticks.

Will post updates this afternoon.

 

[AnitaPeterson]

Holy crap, it works!!?

You all had good suggestions - I hadn't paid proper attention to the RAM compatibility.

After looking once again at the manual, I tried a known good power supply AND a DDR2-675 (PC2 5400) stick of memory. The machine booted up immediately, and I was able to identify the processor, too: a Quad-core Q6600!

I'll try to get this checked and double-checked over the next few days.... but so far I am completely blown away by the discovery: once cleaned and properly set up, perhaps with extra hardware added, this machine would still be current!

Looks like all the existing parts are OSX compatible, too - I might even turn this into a Hackintosh...

 

[vailr]

According to Asus' website, that board should be capable of using DDR2 1066 memory.
"4 x DIMM, Max. 8 GB, DDR 1066*/800/667 Non-ECC,Un-buffered Memory"
Also: that CPU needs a good cooling fan; it will run fairly hot.

 

[mfenn]

:thumbsup: Glad you were able to get it working!