Changed CPU on my laptop but monitor won't turn on

I have an Acer Aspire 5100 and it used to have a single not dual amd turion 64 2.0 ghz cpu socket s1. i bought a amd turion ii ultra 2.5 ghz socket s1. I installed the cpu and turned everything on. The power light and fan look and sound like they are running but the monitor wont turn on. i switched to the old cpu and the monitor turns back on but not with the new cpu. I dont kow whats wrong with it and why the monitor wont turn back on with the new cpu. Please help
 
The handbook for the Aspire 5100 you can find here in PDF format says:
Platform • AMD Turion™ 64 X2 dual-core TL-50/TL-52/TL-56/TL-
60/TL-62 processor or higher with 1 MB L2 cache,
supporting AMD PowerNow!™ Technology and AMD HyperTransport
™ Technology•

Mobile AMD Sempron™ 3200+/3400+/3500+ or
higher with 512 KB L2 cache, supporting AMD
PowerNow!
™ Technology and AMD HyperTransport™ Technology, 64bit OS support.

even though the new CPU is the same socket doesn't necessarily mean it will work with that system. Other times it may work but requires a BIOS update to develop compatibility for the CPU. Your best bet is to talk to ACER directly about whether or not that CPU is compatable with that model.
 
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