Computer Help

[blageo23]

Computer:
Dell Latitude D500 Notebook

I noticed the thing gets pretty hot when on for a long time. Then I noticed that the fan was not working. So i ordered a fan and put it in. Before putting it in the computer worked fine, a little slow but worked. Im done putting the fan in and now the thing doesnt boot up.
The computer turns on and the DELL screen pops up and the load bar goes to the end and then a blank screen pops up with a blinking curser at the top left corner. And now the computer just beeped at me and now says
"Hard disk read failure- No bootable device--strike F1 to retry boot. F2 for setup utility"
What the heck. I know i did remove the hard drive does that matter? Did it whipe out all the memory or something?

Thanks in advance for your help