So, I reattached the GPU/HDs and on startup I got a message saying the my overclock had failed and to reset it. I tried removing the GPU and my hard drives and the computer booted up and didn't shut itself off. Hey guys, thanks so much for the responses. If you for example added a GeForce GTX 580 to an old system with an already starved power supply chances are it won't suffice and as a result your computer will refuse to boot all the way. Anything over 400W and you'll be fine to run pretty much any single GPU setup, 300W should probably be okay for that as well, at least to boot, but I won't guarantee it. It usually says a number on the side, for example 550W. Just to make sure, how powerful is your PSU (Power Supply Unit)? *Your PSU is not powerful enough to supply the added component (should only be the case if it's your GPU, nothing else really draws a lot of power). If it doesn't boot at connecting a new component, your issue is most likely one of the two following: Add one component at a time and leave useless things like an extra HDD or a sound card to last. If it seems to boot without issues (fans spinning, all lights on etc) add another component (RAM or GPU). Keep all fans connected, especially the CPU fan as it will refuse to boot all the way without a running CPU fan.
![laptop turns on and off laptop turns on and off](https://i.ytimg.com/vi/XX6QEj2yZhU/maxresdefault.jpg)
If that doesn't work, try removing all components but the motherboard and the CPU. The most common problem when you've installed a new component is that you've either knocked a cable loose or simply forgot to attach a new one.
#Laptop turns on and off manual
Check your motherboard manual for POST beep codes for your specific motherboard. No beep or several short/long beeps can indicate hardware failure. One short beep generally means that the POST has passed and that it will continue booting. If your computer does not even pass the POST (Power-On Self-Test) it's most definitly a hardware failure.