Messed up Graphics

I just got a Saturn from ebay, it looks great almost brand new. It just doesn't work like it's brand new. I plugged that baby in connected it with an rfu switch and turned the power on. I have to set the language, time and date. Then the Sega logo appears, at least some of it. The Sega Saturn words are there unfortunately the logo isn't. Virtua Cop loads up, it shows the press start screen. The graphics are totally wacked, only showing ground and the sky. Basicly what I'm saying is the graphics are just messed up the 2-D stuff seems okay the 3-D though either doesnts how up or looks like crap. I'm hoping it's a battery problem but I'm not sure. There was this one time the graphics were absolutely fine though but then after that it returned to its old ways. Anyone have this problem before?
It really doesn't sound like a battery problem...

It could be a power supply problem or something more serious.
I've seen similar problems with one of my Saturns...mine is affected by the screen resolution though. Best as I can determine, there is a hairline fracture somewhere on the main circuit board - try wiggling the video cable around in the socket and see if that temporarily fixes the issue. You could also try gently flexing the motherboard by applying a little bit (and I mean a little) of pressure on the cart slot while the machine is on.

In my case, I haven't found a solution.