With respect, it sounds like:
– One of the PSU’s is bad and as soon as you try it, it kills the Genesis. Take one of the official PSU’s, replace the capacitor and check it on a multi-meter to make sure it’s outputting proper voltage. Then ONLY use that PSU.
– You need to leave the CXA’s in and only lift RGBs out. Removing the CXA will cause the Z80 to loose timing after like 20 min. We haven’t researched other ways to fix this yet, as leaving the CXA in doesn’t add any interference.
– Maybe the two other boards are interfering?
– I doubt the 7805’s are dead in all consoles (unless maybe the PSU killed them?), but it wouldn’t hurt to try replacing those as well.
Other than that, I’ve tested at least 50 consoles with either the Voultar board or Triple Bypass (3BP) and all are still working flawlessly.