Sony PRS 650 vs PRS 350 CPU

[yoanna]

Hi, I'm new here, so I really hope I'm doing this post right.

I've got a Sony PRS 650 that apparently has a broken CPU (or so the guy at the repair shop told me. I still don't see how the screen is frozen and the battery charges for 10 min then stops then starts again if the CPU is the cause, but I guess that is a different subject).

I'm wondering if anyone knows where I could find the exact CPU specifications for both Sony PRS 650 and PRS 350 or if anyone knows them by any chance. Or knows if they would be compatible. I couldn't find this exact info anywhere.
I'm thinking about buying a broken screen Sony on eBay to fix my broken PRS 650 (since paying £65 is not worth it imo) but I can only find PRS 350 atm and I'd like to avoid a useless purchase.

Any help would be much appreciated