jadberro wroteif you change the solder yes , if you just re-flow it , the problem will come back .
Ding Ding Ding
There's your answer.
As for playing for 6-7 hours, well ive benchmarked some 360's before, left them for days, once i left one for weeks. Of course i had a back just in case the power cut.
Like i said, the problem itself lies on the cooling down, and there is NOTHING you can do about that. Jaspers seem to be rid of the problem. Most 360's ive delt with that had the damn problem were falcons. Yet again, this RRoD stuff is basically completely random, it may happen and it may not
What MS have done is used shitty paste to clamp these x-clamps down (im sure it has nothing to do with beating the race to release their console beofre Sony's PS3) anyway basically to fix this you have to clean them, and apply Arctic Silver (like i said google is your friend here) and then re apply the clamps back onto the motherboard. Make sure you press down hard.
Things you can do to "prevent" it is to keep it well ventilated, "inno mat hata tahit el dvd player wat sakir 3leiha min kil el maylaaat"
and regular dust outs would help.
P.S Sorry for the long reply