I'm sure you get a lot of these, but I'm at the end of my rope so please bear with me.
The problem started some months ago, actually. I'm running a Windows XP (32 bit) desktop. At the time of the original problem I was using K8T-Neo V motherboard with a 2 gig athalon 64 (at least, I think that's what it was). I had a gForce 6 series 512mb video card, one stick of 1 gig ram (I can't remember the specs on it), and a 120gig hard drive (I don't know the specs on that one either but I think it's a western digital). I was running a wireless optical mouse, a USB keyboard, and a trendnet USB wireless-ethernet-adapted.
During a year at college I accidentally broke one of my rear USB ports, the little plastic tab snapped. No big deal, I had three more. It wasn't until later that this came back to kick my *censored*. I moved to a new apartment and in my haste to set up my computer jammed the USB keyboard into the broken slot while the computer was on. Dumb, I know. The computer shut off instantly. I unplugged the keyboard and turned everything back on. It booted fine and got to Windows, but I couldn't get it to recognize any peripherals; not the keyboard, not the mouse, not my wireless ethernet adapter.
I thought that, perhaps, I could just get away with using a serial cable keyboard, in that case. Wrong. I picked one up and plugged it in, no dice. Now, this may be because the little plastic tab that makes sure you orient the pins properly broke, I'm not sure. However, when I would plug the serial keyboard or the ethernet adapter into the back, their lights would flicker for a moment and then go out. I figured I must have somehow cooked the south bridge. No problem, I just need to to replace the motherboard, everything else is still good. Right?
Wrong. After some searching I managed to locate the exact same motherboard and purchased it. It arrived, I swapped all of the parts into the new board and powered things up. This time my computer failed to post. I tried removing components one by one and adding them back in. I tried booting up with the keyboard, without it, with ram, without it, with the hard drive, without it, with the graphics card, without it, and various permutations of that. Still no luck.
Admitting defeat, I got all new parts (except for the case, which seemed to be functioning fine). Now I'm running a 2.5gig quadcore Phenom 9850 AMD2+, a 750SLI nForce motherboard, an eGeForce 9800 GX2, a Silent Knight cooling fan, four 2gig sticks of OCZ RAM, and a 1000watt Prudent Way Superior Plus power supply. All parts are listed as being SLI compatible.
I plugged everything in and turned on the machine. The LEDs on the motherboard came on, indicating that the four memory slots were occupied, I assume. The fan turned on and the graphics card's internal lights came on. A small digital display on the motherboard says 88. It still won't post. I've tried disconnecting the hard drive and starting again, but it won't post. Clearly the power is flowing. Now, to complicate matters, I haven't quite figured out where to plug in the speaker on my case, so I can't tell if I'm getting a post code.
What puzzles me is that this is the same problem but completely new hardware. The only thing that remains the same is the case. If at all possible I'd like to avoid trying to remove components, especially because I don't have any more thermal grease incase I have to remove the fan. In addition, there is one odd thing, the stick of RAM closest to the fan presses against the fan's housing, although the only part of the RAM that touches appears to be some sort of cooling apparatus. I'd prefer not to remove this stick unless it's the problem, since I had to install it before screwing in the fan's housing to get everything to fit. Any ideas?
