Mac Pro Blurred Lines on screen

Hi All

Pretty sure I already know the answer to this which is going be failed logic board but thought it was worth asking anyway.

Have a 2010 Mac Pro which has been fine until recently. It wouldn't boot to the OS one day and there were blurred lines across the screen. Thought it may have been the hard drive so had a spare one lying around. Booted up, no blurred lines so put an OS on it and thought all was good but day after same thing. Now I can't get it to do anything. Could it be the graphics card or is it most likely Logic board?

Thanks

Martyn

Yeah it starts up but you can very rarely get it to go any further than the boot screen. Interestingly I reset the pram just now and managed to select the recovery partition to reinstall the OS and even though the screen stayed on the boot screen with a load of lines down it I could hear the sound come out the speaker asking me to select a language.

The only thing I don't have spare is a GPU and don't want to buy one and find out that doesn't fix it.

Will apple be able to test the GPU if I take it to the Apple store, don't fancy taking the entire Mac Pro to the apple store?