I just bought a new GT 640 2gig Graphics card for my system but after installing the card there is no display via the DVI-I port (using an DVI 2 VGA adaptor). There is a beep from the motherboard so I presume the board is is detecting the card ok but could the problem be the DVI port? it has a mini HMDI port but I do not have a suitable cable for this, trying to source one but I do not want to waste money on a new cable if the problem could be something else. The card specs is asking for a minimal PSU rating of 350watts with 20 amps and the +12v rail, I have a psu rating of 450watts but only 15amps on the +12v rail, could this be the cause?
Why would you get GT640 if you can get 7750 with more horsepower for the same or even less $$? Don't tell me bc of physx.
Your PSU is fine. Try to refit the card into the slot. If that does not help try different PC if same thing happens RMA the card.
I update the graphics card drivers today and now all I get is is yellow/blocks across the screen (see image) the pc boots up fine to windows login and once I've put in my password the screens does this. I've tried un-installing the new driver and installing the old one but I still get the some screen. when I leave it for a long while the screen flashes and returns to windows desktop but the resolution is set to 640x480 and the tab to chnage this is greyed out. any ideas?