system heats up

hi.. am usin a P4 intel chipset motherboard 845GVSR wit 236 ddr1 RAM.. whenever i try playin games like NFS underground2 or project IGI 2; the CPU starts makin more humming sound as tough the fans r runnin much faster.. is it the thermal problem??? plz do giude..

 

Those games are probably overworking your PC. You barely have enough memory to run Windows, then you add some games on top of that and things will heat up. There's some good free temperature monitoring programs available (here's one http://www.majorgeeks.com/Core_Temp_d5665.html) that will watch your CPU temp. Anything under 55c should be OK. You should definitely double your memory (at least as a minimum) and add a video card to take some of the load off the CPU...
...and welcome to MajorGeeks! :major