I have recently inherited a MacBook Pro which occasionally reboots at random. It has 4Gb Ram (2X2). AHT is consistently showing a 4MEM error - e.g. '4MEM/66/40000000:0xa1e45898'
Diagnostics so far:
- Re-seating/cleaning modules - same 4MEM errors.
- Swapping modules between sockets - 4MEM error with different 0x value.
- Testing modules individually - no errors (in either socket).
The above seems to rule out the memory modules or the sockets. Errors only occur when both modules are plugged in. Could this be a timing problem between modules? (Original Apple memory).
I have tried resetting PRAM and SMC - same errors occurring.
Any suggestions as to where to go next most welcome.