Its a good card. Maybe it is really has a problem. Or..
Perhaps you should disable: "turn off monitor" feature in screensaver options (or set it to never) to avoid your computer to come to this state. Another option is setting your computer to "hybernate" just a few minutes after screen saver starts. See what's happen with these setting and take a conclusion.
Hope this will help u..
thats not the problem because when i had it on my tv i had it on hdmi which doesnt turn off unless you turn off your tv, and it lost input signal out of nowhere