Update: bit of an old thread this but info could still be useful.
Managed to source a Core 2 Duo 2.2 800fsb 4mb for £25, but fitted to Acer 7720G, its much better to multi task with than the Samsung R70 with the 1.8.
Also sold the Samsung as didn't want that onboard 8400gs to fail.
((but i still have the service manual and schematics .pdf)) if any other R70 owners need a copy.
Cheers
Ninja