Computer Freezes/BSODs but gets fixed by moving RAM???

For ages I was struggling with an issue where my computer would go into numerous freezes and BSODs. I tried many things but nothing seemed to work. Memtest cleared my RAM as being fine. But bizarrely I can temporary fix the issue with the following.

1) computers starts to freeze BSOD...over time it gets progressively worse

2) with power lead out, open up the computer and switch the RAM sticks into different slots.

After that my computer will be fine without any errors for approximately a month, then the faults will start to happen again, so I play musical chairs with the RAM again, and its fixed for the time being.

It's not a huge annoyance (changing RAM slots once a month aint so bad) but it's very strange and I don't know what's going on. Does anyone have any theories???

Corrosion.
Could be that the plating on either the sticks or sockets is at issue here. By unplugging-replugging you are wiping the contact surfaces. There are several chemicals on the market that are both contact cleaner and lubricant. If you use it-only put it on the RAM contact surfaces-nowhere else. Also-used compressed air on the sockets and do a general cleaning of the machine prior to reinserting the RAM.
YES-I do know that Gold is not supposed to corrode, however if it is in any way damaged the underlying surface (copper) will.
Good luck