A friend of mine built a desktop today. The pc started fine, the bios loaded and then started installing W7. The preloading part of W7 got stuck near 1/3 or the bar and waited for a while then decided to turn off the pc and start it back up. After that there was no video what so ever. Any one have any tips or ideas on whats going on? Thanks in advance. :)
The pc has 1 2gig ram stick, 1 500gig hdd, a 8600gt, athlon 2 cpu, dvdrom and a 650 power supply.

Disconnect the hard drive and see if the computer will POST. If it still does nothing (no beeps, no error code on the motherboard, etc) then most likely there's a problem with either the CPU or the motherboard, probably the motherboard (failure rates around 5-10% aren't all that uncommon). However, double-check that indicator lights are on and fans are spinning when you turn on the computer, just to rule out a PSU problem. If it does turn out to the a bad motherboard then just return it for a replacement (regardless of the return policy of the place you got it from, a 1 year manufacturer warranty is the usual standard).

We did disconect the hard drive, even removed the ram and no beeps. The lights and fans were spinning too. We found it really weird since it turned on once normally. If i am not mistaken the keyboard lights should turn on if i press num lock for example, with the pc on.

Will double check the stuff tomorrow just in case with a rested head. Thanks for helping out again with this stuff.

sounds like you fried something. (motherboard, or CPU). If you have a spare CPU maybe try that (but make sure you have the cooling attached properly.)
not that i know much about this kind of thing...

Worth checking to see if the memory is meant to be in a pair?

Dont only remove memory but, remove the video card too, see if it beeps, a video card not properly seated will give you no beep boot sometimes, then reinstall the video card and look if it is properly inserted at both ends, install memory modules and boot again.

A low tech solution but have you removed the battery from the motherboard for a few hours? That can solve a lot of Bios related problems.

Most motherboards these days have a BIOS reset button or jumper on them; accomplishes the same thing as removing the battery, just easier and without the waiting.

Thanks for all the suggestions. I brought his PC home and started exchanging parts between his and mine. Turns out his ram was bad and was not letting the pc boot.

Interesting, I'd have expected there to at least be some kind of error code if it was the RAM. Anyway, glad to hear it ended up being something simpler to replace than my guess at what the problem was.

Different bios have different behavior but yes, usually, you should get error codes (beeps) for bad memory/ bad memory bank.

Yeah it was weird that it wasn't beeping or anything. Ill give you the rep since you had the most shots at it.