Dead motherboard?

bass_junkie83

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Last night I needed to move my pc to move it out the way while I fitted a radiator. Turned it off at the wall and took it away as I have done countless times before, it was not running at the time.



Upon putting it back it refused to turn on, no signs of life at all, fans, lights, anything.



Pulled out the PSU and tested it on its own and it turns on fine. So reconnected the PSU, removed everything else from the mobo (cards, ram, screen keyboard and mouse). It would then power up but was giving a consistent series of long beeps. Can't find a beep chart in the manual but I believe it refers to either a memory or overheating issue. As I have removed the ram I assume its memory.



So, I put it all back together, everything installed again except for a couple of expansion cards I was not using anyway. Powers on but still gives the same beeps. Pretty sure it isn't overheating as it hadn't been run for any amount of time previously to heat up at all, but maybe a temp sensor issue? Removed the CPU fans and removed a small amount of dust from the heat sinks and put the fans back on.



Now it wont power up again like it did at the beginning, no beeps or anything.



Mobo is a supermicro x7dbn. Is it dead or could there be something else?
 
How many RAM sticks are you using? If more than 1 have you tried booting the machine with just on stick installed?

I had a similar issue a while back where my PC would not boot with two sticks of RAM installed (multiple beeps too) when I took a stick out and ran just a single stick it booted fine.
It turned out i had a fault RAM stick which a replacement solved.

It may not be the same as your issue but no harm in trying the above.
 
I have two stick in, haven't tried it with just one so will give that a go.

It's getting on a bit now, around 7 years old so it's been on the radar for being replaced. But the timing couldn't be worse!
 
I have two stick in, haven't tried it with just one so will give that a go.

It's getting on a bit now, around 7 years old so it's been on the radar for being replaced. But the timing couldn't be worse!

Sods law as they say!
When trying 1 trying it in different slots as well just to rule out a a faulty dimm slot as well.
 
Will do, thanks for the advice.

In the mean time, i best start looking at a replacement should it turn out to be terminal.
 
Remove cmos battery. The constant beeps sound like a bootloop or a boot sequence error. Reseating all cards and ram etc after pulling cmos, resetting using pins on board or clrcmos button (should it have one) and rebooting may fix the problem.
 
I did replace the cmos battery last night, but didn't do anything else to reset. Will check the manual and see if it says anything about reset pins.
 
How did you test the PSU?
Did you try it in another machine with some load on it?

Until the PSU is triaged, I wouldn't point suspicion at anything else...
 
How did you test the PSU?
Did you try it in another machine with some load on it?

Until the PSU is triaged, I wouldn't point suspicion at anything else...
A bit of late night googling said to remoce it from the machine and link the green wire to the adjacent black, When I did that it lit up.

From that I deduced that the mobo was not switching on the psu.
 
The output voltages need to remain within tolerances once there is load applied to it.
I've done static tests on PSUs which they have passed, but once load is applied voltage drops occurs and you get an unbootable system. This will quite often results in motherboards bleeping when you try and power a box on.

RAM failure is a distinct possibility in a 7 y/o box, but PSU failures are far more common.
 
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