Here are the minimum system requirements to run Left 4 Dead smoothly and efficiently without any crash, freeze, slowness etc. on any computer;
Minimum System Requirements:
CPU: 3.0GHz P4, Dual Core 2.0 or AMD64X2 (or higher) RAM: 1 GB for XP / 2 GB for Vista GPU: DirectX 9 compatible video card (Video card must be 256 MB or more and should be a DirectX 9 compatible with support for pixel shader 2.0) DirectX: DirectX 9.0OS: Windows Vista, XP, 2000 HDD: At least 7.5 GB of free space Sound Card: DirectX 9.0c compatible sound card
Please also have a look at other posts under “System Requirements” category to view & check if your computer system is powerful enough to run other games like Left 4 Dead smoothly.