My computer has been running perfectly fine lately, but after returning from work i got back to see both monitors on standby and the computer whiring away as usual. Moving the mouse around did nothing however and pressing the power button did not turn it off. After holding down the power button to manually turn it off i tried turning it back on - the fans powered up, the hard drive light flashed, dvd drive light flashed and the usb mouse turned on and off intermitantly as it always does when booting up,along with the numlock light on the usb keyboard.
Still no sign of life from either monitor however. I tried unplugging one, nothing, tried plugging it into the second graphics card and still nothing. The first thing i tried was unplugging one of the gpu's and rebooting but that made no difference either.
I've tried searching for suggestions and the only solid thing which popped up was to try and reset the motherboard bios. So i took out the cmos battery, waited for 20 minutes before plugging it back in and then booted up with one gpu. Still nothing on the monitor.
There's no indication from the motherboard that it is failing post, it 'sounds' like it is booting up fine, everything apart from the fact neither motherboard sees anything at all. I dont think the motherboard has ever beeped on booting up, but i could be wrong, it's certainly making no noise at all right now apart from the fans/HD. The optical output on the soundcard is also on if that's of any consequence.
I'm at my wits end now and am really hoping someone on here can offer a suggestion, if i had some sort of error message to work with i'd be happier, or if i'd done something that i could undo i'd at least have something to try, but i just don't have a clue what's going on, i can't even see at what point the boot is failing!
system specs (around 14 months old):
Intel® Core™ 2 Duo E6850 Dual Core Processor(3.0GHz,4MB Cache,1333MHz)
Windows Vista™ Home Premium Edition
PCI-Express Mainboard - SLI nForce 650i SLI(C55) - Intel Core 2 Duo/Quad-Core - ATX
4GB DDR2 667MHz Memory -( 4x 1GB )
3x500GB Serial ATA Hard Drive with 16MB Buffer (no raid)
LightScribe Super Format 20x Dual Layer DVD Writer +R/-R/RW/RAM
2 x 512MB nVIDIA GeForce 8800GT - SLi Configuration
24" Iiyama B2403WS LCD Widescreen TFT Monitor + built in speakers
21" Samsung syncmaster
Creative Labs Sound Blaster X-Fi Xtreme Gamer Sound Card (oem)
Creative Inspire A500 - 5.1 Surround Speakers
Logitech Wave USB keyboard
Microsoft Habu mouse
Multi-format Memory Card Reader (matx)
I have no second machine to try any componants in unfortunately.
Thank you very much in advance for any assistance offered, it will be highly appreciated.
 forgot to add, after it has done what it wants to do and the mouse has stabilised withno flickering of its built in led (i assume it gets to the windows log in screen and then stops but could be any step) it instantly switches off after just pressing the power switch, without any pause, shutdown or whatever. in the lead up to that pressing the power button doesn't do anything that i can tell.
Edited by smoiu, 30 March 2009 - 11:43 AM.