freeborn:艾尔莎 X70旗舰版2~显存频率~问题

艾尔莎 X70旗舰版2的原来的参数是
核心频率 400MHz
显存频率 750MHz
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为什么我的:显存频率只有 389MHz ????我并没有去超过显卡!
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RADEON X700 Series Driver 6.14.10.6583

Description RADEON X700 Series
Manufacturer ATI Technologies Inc.
Total Local Video Memory 256 MB
Total Local Texture Memory 256 MB
Total AGP Memory 128 MB
Driver File ati2dvag.dll
Driver Version 6.14.10.6583
Driver Details 8.191-051028a1-027345C-ATI
Driver Date 10-28-2005
Driver WHQL Certified true
Max Texture Width 2048 px
Max Texture Height 2048 px
Max User Clipping Planes 6
Max Active Hardware Lights 8
Max Texture Blending Stages 8
Fixed Function Textures In Single Pass 8
Vertex Shader Version 2.0
Pixel Shader Version 2.0
Max Vertex Blend Matrices 37
Max Texture Coordinates 8
VGA Memory Clock 389.6 MHz
VGA Core Clock 399.2 MHz
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3DMAK05分数是2928~
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AMD Sempron(tm) Processor 2800+
Manufacturer AMD
Family AMD Sempron(tm) Processor 2800+
Architecture 64-bit
Internal Clock 2.1 GHz
Internal Clock Maximum 3.0 GHz
External Clock 263.0 MHz
Socket Designation Socket 940
HyperThreadingTechnology N/A
Capabilities MMX, CMov, RDTSC, 3DNow!, Extended 3DNow!, SSE, SSE2, PAE, NX
Version AMD Sempron(tm) Processor 2800+
Caches
Level 1 128 KB
Level 2 256 KB