well i got another FRAO xbox... i upgraded the ram, and one chip at a time i put it back together and booted it up... everytime it worked fine, after the last one i booted it and it was fine, i excitedly loaded up XBMC to check how much ram it had... 64MB

so i PMed perplex and he said if it boots fine its most likely a dry joint, so i spent ages trying to find it, never getting a FRAO or FRAG just never got it to say 128MB ram, i gave up for the day soon after, and was using the box for a few hours on and off, all up about 6-7 hours later i got my first FRAO, at first it would happen maybe 1 in 5, wasnt too worried, it started doing it more often, and i worked out that if i turned it off and straight back on it would FRAO always, leaving it 2mins was always enough to make it work again, the FRAOs bacame more and mroe consistant, until my theory wasnt valid anymore, it was now only working 1 in 10 or so attempts, and soon after stopped working alltogether, i put it in the cupboard for a week, and it still FRAOS now.
today i spent 3-4 hours cleaning up my ram install, cleaning flux away, checking everything. and it still FRAOs...
does this follow any patterns?
my multimeter isnt here for me to use, so i cant check anything... i think i give up, get another mobo off ebay