Thanks - Here's the deal. I upgraded to and Opty 180 from a 4000+ everything seemed to go fine. Started up computer hardware recognized new CPU and everyplace showed two cores. Went ahead and installed AMD optimizer and chip bios and the Windows hot fix and REG EDIT. So making sure everything was working well went into Quake 4 to see if I could notice any dual core difference. Game seemed good maybe could see it being a bit smoother. Played no problems. But then going to multi player online I couldn't load the game. Selected sever and then it would start loading and then just hang. Would have to open task manager to quit the application. Sometimes wouldn't quite and screen would flash rapidly. Ok so figured I would go ahead and reinstall windows and give it a go as well as reinstalling quake4. No go same problem only when loading online server games. Tried different drivers seemed to progress further into the load but then just hang. So I decided to disable SLI and sure enough that did it. So what is the deal no problem with single core but dual core and SLI no go. Anyone have any suggestions for me...Please... :?: