Games And Their Specs

i have Dimension 8100 Pentium4 1400 MHz 640 RAM

i played Max Payne 1 last year when i had 128 MB RAM, it worked OK......the thing is, do i need to get a new comp to play all the other new high tech games like Sims 2, Half Life 2, Call of Duty, UT, DOOM 3

i know i will need a new video card but will my 640 RAM and 1400 proccesor withstand all those new games

also will the game still work if it says it recommends 1.7 MHz but i have 1.4

your PC should be good for another 8 months to a year if you have a good Video card but when they say Min specs are 1.6 or up it wont run, most of the time Min specs wont even cut it