what the problem to download kernel source from kernel.org and make new one kernel, based on your exist one (in case if you dont want to lost all functionality and option from present system)
With my last laptop dell aptitude 800 something, i have same problem. I have tried to improve GPU by switch on intel agp (as everywhere, including Intel site, have been talking about). Unfortunately, improving wasnt so big. maybe i did something wrong, but Elive didnt work good and fine as i want.
And the only one way to improve is switch off !! a lot of unnecessary plugins and function.
This text doesnt help you
but for feeling you are not alone here
br