How far did you get with your oc?
Have you added any heat sinks to the gpu or ram?
I have had some good success with ATI Tool for oc'ing my 9600xt 128MB. I was a bit worried at first cause I heard that they were not good to oc and could go pop (but this was after I already had it oc'd and it didn't pop).
With ATI Tool I have it up to 555 core and 325 ram. I have added an Arctic Ice rev.3 cooler (lapped) with ceramique compund. I like it cause it keeps most of teh heat out of the case by blowing it right out the back (you do loose a PCI slot).
Next step is to epoxy on some heat sinks to the ram so I can push the ram a bit more.
After that I hear there is a volt mod that can be done but can't find the link at the moment. If interested in doing this type of mod let me know and I'll post (send me a nasty PM or e-mail if you don't hear from me quick enough
Before doing a volt mod I think I would get a second card (9800pro or x800pro) just in case something fries.
BTW on the 'x't versions you have all possible pipes running. I believe it is only the 'pro' versions that may have an extra 4 pipes that are not enabled.
To give you some ideas on coolng here are some wild modded cards from Viper John: [color=#darkred]Link