Hello everyone. I have this problem with my unit currently and while I have a couple of guesses as to what it could be, I want to make sure that I am on the right track before buying any replacement parts. Here goes: A week ago I was installing a new DVD burner after I finally gave up on getting this Sony burner to do what it should. After disconnecting and reconnecting all my IDE and power cables to my drives, I power on my computer only to have it instantly shut off on me. After playing around with it a bit here is the scenario: - When everything is plugged in and I press the power button, the lights on the case flash for a split second and then the whole thing turns off. - This also happens if the motherboard is just plugged in (both ATX and 12v connectors). - The motherboard power light remains on when I power it up. - When I disconnected the 12v (4 pin) connector, the motherboard powers on and remains on but nothing boots (I don't get the standard beep when a system starts up nor any bios screen). - The above is the same whether or not other devices are plugged in. So, from this I have concluded that the problem is either with the power supply's 12v connector and it's shorting out *or* the motherboard has a short somewhere with the 12v female connector. Any one have some thoughts on this? Hopefully I can borrow a PSU tester later tonight to see if the PSU is working properly but I would like to fix this soon. Nick. P.s. I should have mentioned this before but the motherboard is a DFI nf4 DAFG.

Try unplugging everything from the motherboard, including drives, cards and RAM. Then try it with the 4 pin plug connected. Is the video adapter on the motherboard? Do yourself a favor BACKUP! Sorry, I do not check for private messages

Sorry, should have also said disconnect the power plugs from the drives. Do yourself a favor BACKUP! Sorry, I do not check for private messages

I tried that one already and got the same results, sadly. I was really hoping it was something as simple as a bad drive. As for the video adaper, it is not integrated into the motherboard. I don't think that would be a problem either since it is pretty new (like all the components in the case save for a hard drive). UPDATE: I was able to borrow my friend's ATX tester. The P4 connector had 12v working, but not 5v. Of course, the P4 connector is just two grounds and two +12v pins (I'm 95% sure of this but correct me if I'm off). So, I'm assuming that the PSU is working just fine and there is a problem with the motherboard from what I can gather. If you guys have any other thoughts on what could be causing the problem, post them here! I'll order a new motherboard from newEgg today but it'll take a few days to get here. Not to mention if it does turn out to be something else, I can return the motherboard when it comes. Nick.

I'm having the same boot problem actually, although you're seems a little deeper than mine. The whole, starting up and shutting off with devices connected means that your PSU can't kick the current it's being at for at start up for spinning up all the drives and fans and general POST behaviour. The problem however that your computer wont boot with nothing connected (switches on but no POST beeps etc) usually is caused either by a motherboard or a memory fault. If you can try switching in some alternate RAM, it should help rule this out. But I say, the switching off when you switch it on is definitly that your powersupply can't provide the current your system is asking for. I'm having the same problem with mine, it works perfectly fine until i plug in the 2 new hard drives i bought then the power supply just can't cut it so i press it back on quickly before the drives get time to spin down and it works then. Once it's on, it stays on fine. Hope some of this helps. Alias: Neo

Hey guys. Sorry for the late response. I got stuck working on an older project a friend of mine brought to me again. I was able to get another motherboard installed in this machine and it now works beautifully. I'm guessing there was a short on the board that prevented enough current to actually start the thing from even hitting the post (but not enough to cause a right out failure and have no response). Anyway, I totally forgot about POST codes. Actually, this information helps me out on this new problem I've got with my friends case (I'll have another post on that problem in a moment). Thanks, Alias: Neo! Nick.