Nothing but beeps on boot
 

I've been refitting an old computer to serve again, and after installing a new heatsink and the likes, everything looked good. I turned the computer on, and it just ran. I then installed the hard drives and cd-rw-drive, and unplugged the northbridge fan (Piot said it was cool :) ). Suddenly, all I get is a long beep, followed after a few seconds by another beep. The monitor displays "no input device" or something. I plugged the cooler back in, but it stays the same. According to some page on the abit-site, the beep means there's something wrong with access to the display adapter. So I removed it (an old GF4), but nothing changed. Even with all hard drives unplugged (so it's just the cpu and ram that's actually on the board), it just gives a beep.

What could be wrong?

Edit: removed the memory, same deal.

Nevermind, I fixed it. Probably a bad connection between graphics card and motherboard, I guess.

So everything's working, I'm trying to install WinXP, and I get some "code 4"-error. MS-knowledge base-proposed solution: remove PCI-devices and memory, then try to see which mem stick gives trouble. So it boots with mem stick 1, and it boots with mem stick 2, but it doesn't seem to boot with both.

What the christ.

Kay, so the memory thing worked out as well in the end, and I managed to install WinXP, a big bunch of drivers and whatnot, but then I shut it down to finish up the case. I installed two casefans (intake @ 5v, outtake @ 12v, connected with one of them Zalman-voltage cables)(also, I'm out of Nexus 80mms now), and unplugged the Northbridge cooler (like Piot told me to in another, earlier thread, because it's lou-houd as hell). Try to reboot, BEEEEEEP. Again, no signal input in monitor. Replug Northbridge cooler, still BEEEEEEP.

Oh god what. :(

no short circuit somewhere? memory bad memory? PSU problem? so many factors and possibilities

Well, I doubt it's the memory, although it IS a possibility, of course. PSU problem highly unlikely, I used an OCZ ModStream I took straight out of my gaming system. A short circuit is possible, but I don't know enough about electricity to know where to start looking...
Gah, this sucks.

Edit: I removed one of the 256mb memory sticks, and it booted. I switched the one I took out with the one I left in, and it booted. It did, however, give a "CPU is unworkable of has been changed"-announcement at startup, and it detected my 2400+ cpu as 1500+ (it has done that before, though, but I just blamed it on bios flashes then), but a quick enter-bios-quit-and-save fixed that (didn't have to change anything, even). I think I'll run a memtest.

I'm glad it doesn't seem to be a short circuit. Last time I had that, stuff caught fire. :)

Edit2: So far 2 full passes with memtest86 v3.0, no errors. Both mem sticks are in. Wth.
Perhaps something to do with unplugging the northbridge cooler?

Kay, so I unplugged the northbridge cooler once again, and this time, it's booting. But I'm still kind of unsure. Is it safe to unplug the northbridge cooler (Abit nf7-s)? It's just that it's a computer for my sister, and I don't want her to worry about overheating and all them problems.

when you plug in NB fan the PC doesn't boot? que?

Well, no, but both times before, it worked, yet when I unplugged the NB-cooler, it BEEP-ed. So I plugged it back in, fiddled a bit with memory and stuff and then it worked again. So I thought it might have something to do with it (fan failure guard or something). :)

Count the wires of the fan, if there are only 2 then the fan not being connected shouldn't be the problem.

Yeah, it were only two wires, that's why I was so confused about the possibility of it being the problem.
Anyways, it's all fixed now, thanks. :)

And my apologies for being all panicky again.