A week ago or so I turned on my 600XL and... nothing but a fuzzy blank screen with gray and black snow. The last time it was on previously was a few weeks prior where I had been playing games for several hours.
I read about it possibly being the PSU, so I got another one.
It arrived today and, well, there's no snow, but all I get is a constant blue screen. Just running through RF output.
Any ideas? The 600XL has been upgraded to 64k, if that means anything. I didn't do the mod myself, bought it from a member here.