Vista 64 &gtx260 blank screen when logging on

[slasha666]

hi all
I've got a little problem, someone out there might be able to help me with. the problem being that my display keeps going blank when I try to log on to my computer. I got vista 64 ultimate installed, but have the same problem with vista 32. I install vista, everything is fine. next I install chip set, raid, lan, audio
etc. and everything I hunky dory. another reboot and now I install nvidia 185.85 and reboot, boots fine till sign in screen, I get halfway through password and the screen flickers & goes blank. I reboot press F8 to go to vista options and choose vga 640x480, it again goes to sign in screen flickers and goes blank. I'm at a loss why this is happening, since it worked before & it works perfectly well with win XP 32( haven't tried 64 yet), but the problem seems to be that before I can go into display properties either the resolution or frequency changes.
my set up is
P5Q pro
Q6600
Ocz Reaper 4gb
Gtx 260
various hdd
enermax 485w and before you say it, it is perfectly adequate

can anybody help or shed some light onto this mystery

thanks in advance
sascha

 

[pigpicking]

to me it sounds as though your power supply isnt enough but you said it is adequate.... the problem is i had a 1650 pro and i cut it with the 400 watt now i have a 9800gtx and a 700 watt u really need to go and get that power supply theyre real cheap if it isnt the problem you might have a faulty card =) reply and tell me what u think

 

[slasha666]

hi pigpicking
sorted it! install SMSwitch in safemode & set up some safe resolutions and restarted, went blank again hit predefined button and voila the screen is back?
thanks anyway for the input. by the way a had one of those cheap 700w psus
and it blew my quality enermax it's got 2 18 amp rails and is rock steady.

 

[pigpicking]

nice glad u found the answer