Not really.
My old PC (3 GHz Quad + 7950GT) could do full size capture (ie 1680*1050) without dropping below 30 FPS, for 800*600 you'd need much much less. Even if he's PC is crap (which i doubt tbh) you could just record at half-speed or whatever.
The most important parts for frapsing is a dual-core CPU and most importantly fast HDD's - preferable two separate drives or RAID.