Installed a new CPU/heat sink - PC not starting up

[Foxbat25m]

I just installed a new AMD 1090T on a ASUS M3A78 EM motherboard and now my PC is not starting up.


I checked and ensured that all plugs and connectors are connected to my motherboard. I plugged in the PSU cable, and hit the power switch. My motherboard's LED light comes on.

I then press the power button - and nothing. No POST, no beeps, and no fans spin. Only the motherboard light comes on.


This is what I did:


I updated the BIOS prior and the latest BIOS support the 1090T CPU. I've used this PC fine for a month or so with these BIOS.

I turned off my PC, turned off the power and unplugged it. After waiting for a few minutes, I opened it up and unplugged all plugs, video card, PCI cards ect.

I then removed my motherboard. Next I removed a Sunbeam Core Contact 120mm heat sink/fan - this took a bit of effort, had to physically remove motherboard before getting it off.

I then removed my 9950BE and installed my new 1090T and 92mm Xigmatek LOKI heatsink/fan with TX2 thermal compound.

I am concerned the motherboard might have got damaged during the process of removing and installing my CPU heatsink. But the light on the motherboard comes on when I plug in the power, does that mean it is not a motherboard-related issue?

---------
UPDATE:

I put the AMD 9950 back in, and it POST and went into Windows fine. I tried the 1090T again, and it still did not work.

I decided to put the 9950 back in, and now it does not POST with the 9950 either.

 

[GFORCE100]

I'm not familiar with the above hardware but one thing you don't mention is to clear the CMOS. The BIOS should do this automatically if it detects a different CPU than before but there's no harm in doing it manually just in case. If the motherboard has a CMOS jumper/switch then use that, if not then you'll have to take out the battery for some time (can't remember how long it necessary).

Might some stupid but also make sure no pins are bent/missing on the 1090T and it might be also a good idea to check it's not DOA in a different system (friend perhaps?).

That's what I would try.

 

[dpodblood]

Likely the problem is with (a) the motherboard, or (b) the new CPU. Try plugging in your old CPU (yes I know it's a lot of work) and see if you are able to post. If so than there is an issue with the new CPU. Either it's defective, it was damaged during the install, or it's not supported by the board as it should be.

 

[mfenn]

Check for bent pins or excess thermal compound in/around the socket.