hi there! i used to have a system rigged with a p4 1.7g, 512 sdram, 128mb ti4400. first thing you have to figure out is why you want your system overclocked. is it because of slow game speed? ... slow program loading time? that sort of stuff. but i do believe that your 64mb ti4200 is buff enough to reach above satisfactory frame rates. but if your problem is slow program loading time and your system seem to be stuck in one frame or window, then perhaps your problem may not be related with your cpu size. perhaps its the sdrams. if your board supports both sdr and ddr, then it would do you a huge amount of good to switch to those ddrs. 1.7 gig is a fairly descent cpu size. i tried to overclock my 1.7 to 2 gig once. I barely noticed the difference. then i bought a 512 ddr 333,.. thats when things started to improve. quiker loading times, etc. overclocking does turn your pc from a lets say a v6 to v8 engine at no cost. but, you have to remember that you sacrifice stablity for speed in overclocking.