Based on 55nm TSMC process technology, RV620 has 181M transistors and 40 stream processing units. It has 64-bit memory bus width supporting up to 256MB of memories. Radeon HD 3470 is clocked at 800MHz core and 900MHz for the GDDR3 memories while Radeon HD 3450 is clocked at 600MHz and 500Mhz for the GDDR2 memories. Radeon HD 3400 series support Crossfire X, DX10.1, SM4.1, UVD, PowerPlay, PCI Express 2.0, AGP(later stage). Drivers supporting Radeon HD 3400 are 8.44RC, 8.431, 8.45, and 8.47 (Feb).
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