I just got a Radeon 8500LE. The stock fan was loud so i pulled the HS off it and attached a PIII Tualatin HS which is over sized pretty well to the Radeon! It worked great and I proceeded to OC. The max I could hit was 320MHz. I Well I got 9750 3dmarks with it @ 1.7GHz/162fsb/1.65v GPU/MEM @ 321/321 1.87v/3.3v.
In my process of OC'n this setup I found though that I could not hit 162fsb for a little while and then noticed I did not put my chipset HS back on! So from here I realized that maybe I should put a oversized HS on the chipset also! So on the chipset I put a celeron tualatin HS and once again it worked very well!
For these I simply drilled and tapped the HS for a very small size screw aligned with the holes on the mobo and gpu mobo.
For the gpu mobo I have a 60mm very thin fan very low watt spinning with 12v. It is from a apple computer At 320/320 it keeps the radeon very cool apparently and it is silent.
At 1.4GHz and radeon @ 300/300 I still get 8400 3dmarks!
Surprisingy I can up the speed of the cpu to 1.7GHz and still keep the HS fan @ 6v. Between 12v and 6v the temp differences are around like 5 deg. C!
Yes I also did lap the radeon IHS.