I should clarify...

The system isn't locking up. Only wow is. Windows is 100% responsive, the 5 wow clients stop using CPU and their graphics stop updating and t hey stay on screen... you can do anything else you want. End task kills them after prompting are you sure...

PSU is solid and relatively new, the entire system got overhauled twice in the last year so nothing is more than 12 months old, the PSU it's self is an Antec 650w.

I've played for hours on end without any problems with 1 client, however 5 boxing locks all 5 up.. I also have a huge problem with network sync issues, two or more clients that simply won't see what the others are doing and eventually disconnect from server... etc.

No spyware... no malware... I'm perplexed.

All the temps show fine and in normal operating levels.