My graphics card is running slow/weird

[fridge gnome]

I'm running into some trouble with what appears to be a graphics issue.

I currently have two GTX 460s that I bought in 2011 that have run pretty much everything I've wanted to play.

Recently I've been having trouble with the theme on windows 7. It will occasionally only use the windows 7 basic theme , and won't let me switch to anything else. This isn't all the time though, sometimes it will load a black theme, and sometimes it will let me switch back to my downloaded theme.

Another problem that I ran into just today, was that my games are running "jerkily". Minecraft was still showing me playing at 90fps, but it was clearly not running smoothly, as I was jumping around the game.

I've also run into frequent crashes in Far Cry 3, but I recently updated my graphics drivers and that seemed to go away.

Both my gpus are watercooled, and only hit about 40c at load.

Overall, I just feel like my graphics cards failing or something, but they don't seem old enough for that.

I know this is all kind of vague, but I'm really not sure is specifically going wrong.

Any ideas?

 

[Crackadamus]

At a glance it sounds like your power supply might now be delivering enough juice consistently to your cards.