Originally i bought a cheap X clamp kit from ebay and my RROD went away.

.

.

.

for about a week or 2 and then it came back.

So I re did the fix cleaning the cpus and using fresh paste etc and the same happened after 20 mins of play time.

Yesterday I bought an Xecuter kit

(£16) that comes complete with 4 sticky heat pads with a high K value for the chips on the rear of the motherboard along with a higher quality paste/grease and much better bolts

(fit is perfect) and 2 screw drivers

(which i dont need but still handy).

So far so good

- 5

- 6 hours of constant online play

I will update this post if it fails.
