There has been some talks about microfractures/bad solderings on the 68000 cpu, which caused the lose of connection when the cpu socket was pushed over the cpu.
Sounds like that could be it, since it works when the card is not pushed completely into place.
Think that i red somewhere in this thread, that amigakit could help solve the problem if thats where you bought it.
Originally Posted by p@rity
I seem to have a bit of an issue with the socket on the A630/25. I installed a 630/30 on another machine earlier and noticed that the socket had to be pushed to ensure it covered the CPU all the way.
With the 25 version though, if I push it all the way, a click sounds and the A600 doesn't boot (white screen, no disk activity). When I lift it slightly, the system works great and has worked for days. However, this morning it started generating a Watchdog error (caps lock blinking). After wiggling the accelerator a bit, the A600 started to boot normal again and runs solid without any errors for hours on end.
The 68000 CPU legs were cleaned before installation, so I can rule out corrossion. Also, the Caps in the system have all been replaced (properly).
Amiga 600HD (rev. 2B)
A601 Memory Expansion (added and removed to test)
Brand new capacitor set
Classic WB Green Alien
External Rom 3.1 (tested)
Internal Rom 2.1 (tested)