Hi, I have Hp Pro 3500 MT tower system with core i5 3rd gen 3.20ghz 6mb cache 4gb ddr3 1600mhz ram and built in Intel HD Graphics 2500 card. Even old games like IGI 1 are hanging, i have updated graphic drivers and have set 3d settings to maximum performance but nothing is working on other hand i have hp 8200 tower system with core i5 2nd gen 3.10ghz 2gb ram running games smoothly on its builtin card here is my system's detailed configuration