今天刚买的电脑，买家说主频是2.7ghz的，但回家后，我右键点击我的电脑属性，查看主频为1.21ghz，但是在运行中输入 dxdiag  查看主频为2.40ghz
请问这是怎么回事啊？

是不是我被买家骗了？

用户系统信息：Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)

型号是AMD7450

Time of this report: 7/25/2009, 15:39:02
      Machine name: WWW-15F832BCC12
  Operating System: Windows XP Professional (5.1, Build 2600) Service Pack 3 (2600.xpsp_sp3_gdr.080814-1236)
          Language: Chinese (Regional Setting: Chinese)
System Manufacturer: ECS
      System Model: GeForce6100PM-M
              BIOS: )Phoenix - Award WorkstationBIOS v6.00PG
          Processor: AMD Athlon(tm) 7450 Dual-Core Processor,  MMX,  3DNow (2 CPUs), ~2.4GHz
            Memory: 2046MB RAM
          Page File: 333MB used, 3605MB available
        Windows Dir: C:\WINDOWS
    DirectX Version: DirectX 9.0c (4.09.0000.0904)
DX Setup Parameters: Not found
    DxDiag Version: 5.03.2600.5512 32bit Unicode

谢谢