Computer being naughty

[orfajackson]

I just built my PC. Here is what I have:
Operating system : VISTA 64 bit
Processor: i7 Quad processors
Soundcard : Creative Labs Blaster Professional Series Titanium XFI Fatality .65 gig onboard memory
Video card: 9800 GT EVGA 1 gig onboard memory 2.0 PCI express
Ram: 6 gig
Hard drive: 1 terabytes
Keyboard: Microsoft 8000 USB Wireless Entertainment rechargble blue tooth keyboard and mouse set
Power Supply: Antec 750 watt
Mother board: ASUS PST-Delux
Cooling: V8 Cooler Master
Blue-Ray DVD burner: LG Super Multi Blue
Software: Microsoft Office 2007
Case: ANTEC 900 Advanced Gaming Case with 3 fans and one huge fan
Scanner EPSON V500 Perfection Photo 48 bit


Everthing works smoothly and seamlessly.
One baffling problem: Often the computer will not start up. The screen stays black.

So I shut off the computer. (From the power supply switch on back of the case.) Then I upplug the Power Supply. I wait 2 minutes for the capictors to drain.

Then I turn the power supply back on and start up the computer - and it starts up with no problems. Why does this happen?

Thanks, guys
orfa

[lordsmurf]

Power supply, maybe. I've seen that multiple times in years past.

[MOVIEGEEK]

It could also be a faulty power button or connector.

[redwudz]

Are you getting the normal BIOS beeps when it does start properly? And none when it doesn't? No fans, lights or anything?

If so, I would agree with the PS or the power switch. You can test the power switch at the motherboard by exchanging the reset terminals with it. They both use a momentary switch. Or just jumper the switch terminals at the motherboard. Those are all logic level terminals, no damage if you get it wrong.

If that fails, then substitute the power supply. Your setup will run with a 400W PS if needed, for testing. You can also jumper the 'on' terminals on the PS motherboard connector, but that can be risky if you're not familiar with finding the correct terminals.

The front power switch just sends a digital signal to the motherboard, which in turn, operates a switching transistor in the motherboard and that sends the 'on' signal to the power supply. If the front panel switch isn't the problem and the power supply isn't the problem, then the next suspect is the motherboard itself.

I would also recheck all your internal connections on the motherboard, especially the power connections.

EDITED

[INFRATOM]

My guess is your BIOS setting, your RAM setting could be too aggressive or memory incompatible. Make sure sure setting match MB. Flash your bios to the latest. Tell us more about your bios setup, what kind of RAM and it's speed etc. There is also a possibility of finding the boot sector make sure no USB storage device is plugged in at boot, it may want to boot from USB.

[MysticE]

My guess is your BIOS setting, your RAM setting could be too aggressive or memory incompatible. Make sure sure setting match MB. Flash your bios to the latest. Tell us more about your bios setup, what kind of RAM and it's speed etc. There is also a possibility of finding the boot sector make sure no USB storage device is plugged in at boot, it may want to boot from USB.

You might also check what voltage your memory requires and what the MOBO is supplying. You might have to up the default a bit.

[fritzi93]

My guess is your BIOS setting, your RAM setting could be too aggressive or memory incompatible.

My guess too.

I just completed my new HTPC and had a similar problem that developed a few days after loading the OS. Well, actually, a stick of RAM was not fully seated, no boot, nothing on the monitor, no beep, nothing. (It took a lot of force to fully seat it when I finally spotted it.) Then restarted, beep, went into the BIOS diagnostic settings (F12 on this MoBo), okay, back to BIOS and reset to optimal defaults, okay. Then it just wouldn't boot, it would hang on the hardware monitoring page. Tried a lot of things (including a successful BIOS flash) for a few hours. Finally I restarted and hit F8 and got into bootup options. Started Windows and it's been A-OK ever since.