Computer won't boot after cleaning heat sink

[SoDoWarts]

VERY Weird -- After watching several videos I just cleaned the cpu fan and heat sinks on my two desktop computers: an Acer Aspire and an HP Pavilion. I cleaned off the old thermal , put new thermal adhesives on (as directed by Artic Silver) and installed the cpu and heat sink into both of my desktops. But neither computer will boot up. When the Acer is started the the fan immediately kicks into overdrive and I get a brief "no signal" box on my monitor. As well, basically that same thing is happening with the Pavilion either. It starts for a second, the power light goes out but the fan keep going and I get the "no signal" on the monitor.

Any help is appreciated.

[Kunal]

Have you installed the CPU properly into the system of your. I will advise you to check whether it is properly inserted or not. Also check whether any cable might got the loose connection with the same. If still not working then i will advise you to remove the CMOS battery and clean it. Also rub the metallic part of the RAM with the Eraser and then place it properly into the system of yours and see whether all this is working with the issue of yours or not.