Dell gx280 cpu upgrading

[spiderpips]

I am running a dell optiplex gx280 with a Pentium 4 3.0Ghz. To upgrade it i bought the same CPU but with 3.2Ghz. I carefully installed it but when i swich the pc on immediately the fan started to overwork gaining rpm on rpm till i swiched off. I repeated the operation, checking the fitting of the heathsink on the CPU. Still the fan never stopped to accelerated. Has anyone else experienced the same with the same Dell? I never read about upgrade the fan for such a small increase in the CPU.Anyone can help please?

 

[das_stig]

Are you sure its an exact match, P4s come with different bus speeds and memory speed requirements.

Can you give model numbers off chips?