I stumbled across why my triplescreen (And dual screen intrestingly) doesn't work!
And I thought I would share the info, so if any other naive person like myself who thought Nvidia wasn't completly retarded would know what not to do.
Basically all the sockets on the graphic card, and most importantly, on the MONITORS, must be exactly the same as each other.
So you can use 3 DVI cables from GC to monitor, or 3 DVI->HDMI cables from GC to monitor, but you cannot do 2DVI to monitor and one DVI->HDMI to monitor. If you do the latter your entire PC just breaks, and nothing seems to work. Literally all games within 5min 100% guarnteed to crash. (At least for me!)
The intresting part is, even in dual screen setup, and running SLI, I get the exact same problem, but if I use DVI for both GC and monitor, it's fine!
So now my monitor with a broken DVI port (Which is why I was using HDMI on it in the first place) is going to be sent back to get replaced/repair, and maybe just maybe I'll be able to go back to triplescreen gaming sometime this century!
Oh and this is ONLY for nvidia, ATI aren't quite as silly as this.