One card is a XFX 5830, the other is a Saphire 5830. I'm seeming to have crashes when I go to do anything intensive concerning the Saphire card. Is that possibly my problem? I shouldn't have mixed cards?
It could happen, are you using MSI afterburner? I have my cards double up by brand, 2x xfx and 2x sapphire on two rigs.
Try using MSI afterburner and not syncing the settings, uncheck that in the settings box, set the core clock manually for each and apply seperately.
Just because they are the same model does not mean they work the same. Chipset = same, but some of the other features are not.