I wouldn't consider it rock stable. The most stable system I ever had was my last running Win2000 on a FIC VA503+ and I am not quite there yet with my new system. However, my current setup, a 1200 Athlon, A7V133, Radeon on WinXP is getting there. I was having problems with my display and random lockups but fixed it by cleaning up my Radeon's drivers. Other than that I haven't had a blue screen since. Other than that, the only stange thing that I still have happen is that it locks up every so often right after booting. I think there may be something that I load on startup that is causing some problems, but I haven't tracked it down yet. So I'd place my system around eight out of ten on a "stability scale."