sleep and power

installed vista 64 ultimate, after 20 mins pc went to sleep, case went dark,
hit a key neon lights up, punched in password good to go. Well it all
changed, now when it comes back from sleep it reloads vista. I hate waiting,
tried changing it back but no luck. Hibernate, sleep, balanced power plan all
greek to me nothing works. i like the idea of the case shutting down, but not
enough to wait for vista to reload. For now leave on 24/7 with monitor going
dark after 20 mins. Any ideas would be helpfull, tried numerous combinations
for a week and gave up.
Amd 64 X2 4200
4 gigs 3200 ddr
Asus A8R32-MVP Deluxe
His Ati 2600 Pro
Vista 64 Ultimate