Upgrade Processor Dell Dimension 2400

I put a new processor into my computer and now it won’t start. What should I do?

I have a Dell Dimension 2400. I had a 512 MB Ram with Intel Celeron 2.6GHz processor. Then I upgraded it to a 1GB Ram with Intel Pentium 4 2.8GHz Processor. However, when I did my computer went to the desktop screen but unexpectedly restarted and went back to the splash screen. Then it kept on starting up and going back to the splash screen over and over again. Finally after awhile my computer did not start at all. please help!
The processor is not heating up so I don’t think that that is the problem. Maybe something else, i dont know.

Try replace the Ram back to the old 512MB .
If the PC starts , then the new 1GB Ram is faulty .
Also make sure that CPU , Ram is seated properly in socket and CPU fan is running.
Many motherboards wont start if CPU fan fails, to protect CPU.
You can also revert to your old CPU , just to test that evrything is really ok.
If it still doesnt work, then it could be m/board is damaged/shorted.

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