I did not notice anything odd happening with the atmosphere, but I am back on my xp install (dual boot) due to my bogged down install of xp being faster than vista
I might go back to vista tonight, so post any questions you might have.
As for specs,
Asus A8N-SLI Deluxe
AMD Athlon X2 4400+ @ 2.6
1gb Corsair Dual Channel DDR400
Nvidia 6800 Ultra PCI-E (128mb I believe)
250gb SATA (Vista)
320gb SATA (XP)
Its getting a bit outdated, but should still be good for another year or so.