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AutoCAD LT 2011 System Requirements
32-bit Operating Systems
Intel® Pentium® 4 or AMD Athlon™ Dual Core, 1.6 GHz or Higher with SSE2 
technology
1 GB RAM
1,024 x 768 VGA display with True Color
Or
Intel Pentium 4 or AMD Athlon dual-core processor, 3.0 GHz or higher with 
SSE2 technology
1 GB RAM
1,024 x 768 VGA display with True Color

64-bit Operating Systems

AMD Athlon™ 64 with SSE2 technology, AMD Opteron™ with SSE2 technology, 
Intel® Xeon® with Intel EM64T support with SSE2 technology, or Intel Pentium 
4 with Intel EM64T support with SSE2 technology
1 GB RAM
1,024 x 768 VGA display with True Color