PS/2 and USB keyboard will not initialze BIOS

[jcmoney111]

After suffering from a power surge and losing a motherboard, I decided to get a MSI 785GTM-E45. Once I got my system connected back up and after doing a scan disk/restore point, everything appeared OK except my power indicator/HDD activity lights wouldn’t light up(tried reversing didn’t work). Then when I restarted the computer it would only close explorer and everything remained powered up endlessly. After manually hitting the reset switch, my USB keyboard wouldn’t get me into BIOS, so I dug out my PS/2 keyboard and tried but, no go. The ps/2 keyboard didn’t appear to have power at all except for initial connection when system was powered up already. Come to find out device manager wasn’t recognizing the PS/2 keyboard at all once logged into Windows 7. After talking to MSI support for about 15 minutes he said to replace the board because it sounded like a dead ps/2 port. I got my replacement last night and I am in the exact same scenario. I have tried 2 different known working ps/2 keyboards and usb keyboard with usb to ps/2 adapter. Could this be a very discrete problem dealing with something else in my system or bad luck with these boards? Other than that my system is very stable playing high-end games and what not.

Phenom X4 9750
Radeon HD 4890
G.SKILL 4GB (2 x 2GB) PC2 6400
WD1600AAJS 160GB 7200 RPM

 

[jcmoney111]

I have the backplate on and the board is mounted to the standoffs securely. I plan to check if there is any backside grounding. If not could this be PSU related? I had checked the PSU with a tester and everything looked good but, I did get the initial damage through a storm. Could it be fluctuating? I

 

[Onus]

If a storm knocked out your system, other damage is highly likely. What brand/model is your PSU?
Did you reset the BIOS to defaults by moving the jumper and/or removing the battery?

 

[jcmoney111]

Yes, when I clear CMOS I get the "cmos checksum error" and then I have the option to configure or load defaults. Then of course I can't do that if my keyboard doesn't work LOL. So reset SW gets me back to defaults. I have also tried each individual stick of RAM. I had a few slightly bent pins on my CPU til I fixed them and now it sets just fine but, is it possible that one pin could be the culprit?

 

[jcmoney111]

500 watt Antec Basiq

 

[Onus]

Hmmm, that PSU isn't bad, but not great either. Because the storm may have damaged it, replacing it can't hurt anything.
You've tried two different keyboards...I'm wondering if your +5V rail is ok.

 

[jcmoney111]

Right now my PC is stripped down to CPU, Ram, Board, display, brand new ps/2 keyboard, still no response from keyboard at POST. I think I will pick up a PSU tomorrow. I really can't think of any other possibilities.

 

[Onus]

Look for one with full range active PFC (no little voltage switch) and 80+ certification. Antec, Corsair, Seasonic, and Enermax are among the better brands.

 

[jcmoney111]

So yesterday I picked up a Antec TruePower 650W and I still had the same exact problem. I pulled the board out again and started looking for any evidence of grounding and saw a standoff that had been left from a Full ATX board that I had in 2002. I took that out and everything started working. For the first time a blue LED lit up on my board, front panel lights now work, the pc will successfully do a full restart, and my PS2 keyboard works. Thats the first time I ever seen a pc boot while shorted out. The standoff looked like it was touching 2 or 3 pins in the vicinity of my sys-fan. I think it is interesting that it only caused problems to the most basic but, important things.

 

[jcmoney111]

Best answer selected by jcmoney111.

 

[locky88]

So yesterday I picked up a Antec TruePower 650W and I still had the same exact problem. I pulled the board out again and started looking for any evidence of grounding and saw a standoff that had been left from a Full ATX board that I had in 2002. I took that out and everything started working. For the first time a blue LED lit up on my board, front panel lights now work, the pc will successfully do a full restart, and my PS2 keyboard works. Thats the first time I ever seen a pc boot while shorted out. The standoff looked like it was touching 2 or 3 pins in the vicinity of my sys-fan. I think it is interesting that it only caused problems to the most basic but, important things.

Thank you very much for this post and I hope it will help me. I have exact same problem that you had - tried 6 different keyboards (3 PS2 & 3 USB) with no luck. I even went to the store with basic components (CPU, Memory & Case with Power Supply) and they tested for an hour with no luck. So they gave me a replacement of a brand new board on the shelf. I brought it home, installed and the same thing happened again. I upgraded an old board with this one and I begin to suspect there was some problem with my PSU althought it was working fine prior to the upgrade. Your explanation about the standoff makes a lot of sense as I was wondering how can two MBs have exact same problem and MSI quality control even missed this basic feature - getting into bios. If this works, it will save me a trip back to the store to exchange for another one