DVI problem, pc won't start! help needed.

[snowwolf]

System,
Intel 875PBZ Mother board with 2.4ghz 800fsb
MSI Ti 4200 vtd8x video card.
Iiyama AU5131 20.1 inch TFT monitor
Problem: I have my monitor coupled to the video card via the DVI output, I have had it this way for a year now with no problems.
I decided to have a fresh start and format my hard drive, installed XP pro SP1 included, all went on fine, decided to add the extra updates from Microsoft, while doing so, my pc locked up, I had to turn pc off then back on again.
But all it does is turn on the pc as far as just the fans turning on, it will not go any further than that, then it just sits there and does no more.
If you remove the DVI lead from pc, it will boot up fine????? if you add a VGA lead from pc to monitor, it boots up fine????? but the post writing is not central on the screen.
I reformatted the drive and installed windows again, with the VGA lead connected, removed VGA and tried DVI still had the same problem?????
Changed the Video card, still had the same problem.
Changed the motherboard, still had the same problem.
Changed the hard drive and reformatted, still the same problem.
Me now thinks it's got to be the Iiyama monitor, Iiyama have excellent costomer service, they said they would exchange the monitor, that arrived today, and guess what, I still have the same problem!!!!! me know pulling out what hair I have left.
Can anyone help me with this problem or can let me know where I can find help on this.
This has all started from installing windows updates from microsoft????
PLEASE HELP.