This should be an interesting issue for you all to tackle...

I was having this same issue with my computer (starting about a week or so ago), so I tried the standard things (clearing the CMOS, removing the battery for five minutes to wipe the CMOS, switching out hardware piece by piece, etc...) to clear up the issue, but to no avail. Since my computer was a socket 478 system, and I saw a sale in the ads, I decided to upgrade the processor...which means upgrading RAM as well (and, in this case, SATA hard drive and video card [no on-board video, and I didn't have a card that would fit in] as well). So...I bought the following:

• Motherboard: NFORCE6M-A
• Processor: Athlon 64 X2 Dual-Core
• RAM: 4x A-Data DDR2 800(5) 1GB sticks (that nice dual channel aspect and all)
• Video: GeForce 8500 GT 512 MB
• HDD: 160GB SATA Maxtor Hard drive

Yeah, yeah, yeah...decent (my bank account hurts...).

Anyway...the problem...:
I plugged everything up (attached an old IDE HDD first to see if I can use that before going out and buying the SATA), turned the machine on, and it POSTed just fine. It went into XP Pro, but then I got the blue screen of death...arg... Okay, so I booted into safe mode. I got further (it allowed me to sign into the Admin account), but before the desktop came up, BSoD again... Okay...I went to another PC and made sure that XP Pro was compatible with a 64-bit processor. Found out it was, so I was stumped... Said "screw it" and got an SATA HDD anyway (I only had one IDE connector on the MB anyway, which I needed for the CD-Rom). Came back, plugged in my SATA drive (without the IDE HDD) and CD-Rom (DVD+-RW, but whatever), turned on the PC, and my monitor was blank (CD-Rom also doesn't power up when it is plugged into the MB, but it does power up when I pull out the IDE cable...I've switched cables to make sure that wasn't the problem, but the six or so cables I have doesn't seem to matter)... Checked the video card (made sure monitor was tightly secured and that the card was too). Scratched my head, then turned on the PC again. Same result... Okay, I remembered reading somewhere that installing new HW may require clearing the CMOS... Okay, no prob. Did that, restart, blank screen... Pulled battery for five minutes, restart, blank screen again. (I noticed a spot on my MB that says "CMOS_Wipe"...of course, it's just three metallic dots on the MB, and I didn't mess with them...but worth mentioning.) Okay...disconnected HDD and CD-Rom and three RAM sticks...leaving just the VC, CPU, RAM, and fan/headsink. Okay...blank screen upon restart again. I've also switched out every stick of RAM to make sure they were all good. This was all last night (I bought and put together last night, since I've been without my PC for a week...and feeling deprived, lol). My twin suggested to me that it may be a HW virus that jumped from my IDE HDD to my MB. If that's the case, and it corrupted the BIOS, is there a way to "blast" the Bios chip (which I don't know where to find that...) and reinstall the Bios back onto the chip (or just purchase a new Bios chip and from where)?

Oh, did I mention that there aren't any beeps (no sound other than the CPU fan, case fan, power supply fan, and the HDD)...?

I know...it's a lot... My computer (pre-64-bit CPU) did the exact same thing... I think it's odd that the computer would work just fine an hour before putting in an SATA drive, then just stop...

I would say I'm frantic, but I'm more depressed at it's dying state...lol.

Suggestions? Thanks in advance in any case.

Maybe the motherboard is DOA its not unusual.

So...the MB worked, and then died...and is DOA? Hmm...I wonder if just getting it replaced would fix it...

Edit: How rude of me...

Thanks for the tip, I'll give it a try. In the mean time, do you think there are any other suggestions or tips I should try? Thanks.

i dont know its not really my thing

but yeah the motherboard thing can happen , sometimes when it heats up during first use defects such as cracks in the capacitators widen and eventually cause issues

can you try with another power supply unit?????

Reading your post;
You plugged a hdd in that had xp on it and tried to boot it up?
Did you run repair on the OS first?
I just have to know--rik
And I am think power supply too

I couldn't run the OS disk along with the IDE drive (one IDE port). That's actually why I decided to just get a SATA drive and then install XP x64 on the SATA (and then pull data off the IDE via an external case).

I've used three power supplies (one I'm sure is dead, one old enough to be dead, and the third that I bought last week, which makes everything turn on [including case fan and CPU fan]).

Of course, I'm not sure why not repairing the OS first would cause the machine not to run anymore about an hour after I tried booting with XP Pro.

P.S. I went ahead and switched out a few power supplies, including the one to the computer that works (that I'm accessing internet with). Does the same thing (SATA boots up, but no display and DVD-Rom doesn't power up if connected to the MB). Yep...stir crazy...

(Thanks for the tips... Think I should just go out and buy another power supply, or just try and get the MB replaced?)