problems putting together old parts

[Davegod]

Having rebuilt what's more or less my PC of about 2 years ago, it doesn't work.

Once everything internal was connected I switched it on as a test, all that happens is the power LED blinks on and the cpu fan gets about a 1/4 turn and it blinks back off again (it stays on, say, half a second at most; the case and psu fans don't even get a chance to start up).

The MB is an Epox 9NPA+ which as a status display thing, when it blinks on it shows FF - which I think it used to show back when it was working perfectly as my main PC. [edit: rest of specs are a AMD3400+, 2gb ram, 9800GTX, couple of PATA HDD's and a CDRW on some no-name 700w psu]

I've unplugged everything unnecessary, reconnected the power cables, cleared cmos, then ran out of ideas. Anyone?

 

[Davegod]

realised there was that one thing that I hadn't unplugged, but y'know a PCI slot USB cable can't POSSIBLY cause this issue.

Well apparently it can. Hopefully all OK now.

 

[mindless1]

What's a PCI slot USB cable? It seems as though your PSU was shutting off because whatever that part is, was shorting a power rail.

 

[Davegod]

it's the cable that plugs into the usb headers on the motherboard, putting USB connectors on the back of the PCI slot covers. Dunno if they have some proper name.