Ok i put it all together it's kinda late.. p4 2.6 800 fsb msi neo2 ls mobo 2x512 kingston hyperx 3200 80 gb seagate hd ok.. the problem is.. i bought a generic case from accupc.com and it has a 420 watt ps. Well.. although i checked jumper for on switch and all my connections they seem to be fine. The fans jump for a split second and don't make a full turn and stop. But.. nothing seems to actually power on. Please help. Any thing would be good specially since this is for a friend and not me.

I would first start looking for short circuits. The Power Supply is finding a problem and cutting itself off as it is meant to do. Check the mounting pillars? Are the insulated from the the motherboard. Did the case come with mounting pillars already installed. Check that one of then is not being used and is shorting against the underside of the motherbord. If that fails, disconnect everything except, CPU, memory and video display. See if the works. You can try removing the memory altogether. You should then get a series of bleeps if that is the problem. This may be obvious, but check the CPU is in fact installed the right way round. Stuart

Well.. i looked at the cpu again.. it is installed correctly. The thermal paste is spread correctly so i know the fan has contact. The fan is plugged in the right socket. The cpu has no visible damage.(yet) As for the power supply mounting brackets the only thing i see is one piece of metal that it screws to. But the mobo plate seems completely isolated from the power supply. There doesn't seem to be anything visibly wrong. I disconnected every but motherboard/cpu/video card/memory. No bleeps at all. :( the fan barely twitches. I rechecked the jumpers those seem fine. Is there a way to check the powesupply without taking it out and using it on another system? Any other advice is welcomed, this is stressing me out cuz it's not my pc.

I doubt if it the power supply, although you can take it out and check it in another computer. They are all pretty much the same. Its something on the motherboard that is shorting. Take the mothboard ot of the case and check it on the bench. If it then works you definately have a short circuit. Stuart

It sounds like you might have one of the motherboard mounting studs in the wrong position and it's shorting out the motherboard. Removing the motherboard from the case as suggested above is a very good idea.

Thanks for all the help.. it was shorting itself out due to me being sloppy and completely forgetting the spacers. This makes me extremely happy :P