I just installed new CPU cooling, and when I was plugging in the new fan to my motherboard i had to remove my video card, now when I turn on my computer, The new CPU fan works fine, the video card fan comes on, but I get no display. I tried a different video card and still no display.
Did I damage my PCI express slot while removing the video card to plug in the CPU fan? or could it have something to do with a faulty CPU installation? or my power supply isnt good enough?
400W power supply
just installed the zerotherm BTF90

I appreciate any help I can get, thanks

Mozz

Post all of your specs, including the PSU model. It's unlikely that you damaged your PCIe slot unless you used a crowbar. Did you remove the CPU when you changed the heatsink?

mobo - ASUS P5LP-LE
video - 7600gt
processor- intel pentium d 820
PSU - liteon 400W

and no i didnt remove the CPU, but i unclipped it to get some old thermal paste

I'm guessing that is an OEM box like a Compaq or something? Everything worked as spec'd out and you only changed the HS? If so then the PSU, although not very good, is probably not the cause.

I'm assuming that you get nothing, no hard drive LED flashing, no OS boot etc.

Check the 4 pin CPU connector, to ensure it is connected.

Try resetting the BIOS (CMOS). Usually, it involves shorting reset pins for 5-20 seconds, consult your manual, or the appropriate website.

Try removing your RAM or video card to see if you get any POST (Power ON Self Test) failure beeps. Be sure you have a speaker in your case. If you remember hearing a beep when you booted in the past then you have one. If you don't get several beeps to indicate a problem then you have a real problem.

If you unclipped the CPU and it came up from the socket when you were cleaning it, then, as a last resort, you may have to remove the CPU and check the socket on the mobo, with a magnifying glass, to ensure that none of the fingers are bent. It's very easy to tell, because the light shines off them different. If they are, you can straighten them with a large pin, paper clip, or very small screw driver etc.

yeah its originally a Dell 4100y
nope no display what so ever
gonna check the pins as a last resort
not sure how to reset BIOS but ill look into it.

CPU cable plugged in? Any post beeps with RAM or VGA unplugged? I'll do a quick check for the CMOS clear.

Dell Dimension 4100 System Solutions Guide Given the information for clearing passwords, if it won't get you into BIOS you should also try removing the battery for a little while. Clearing the CMOS probably won't solve your problem anyway, but it is one of the steps.