My system wont boot?

[Superslinky]

Ive been trying to get this computer to boot for days now. I built it out of a few different computers and now when I start it up, I can hear the hard drive and fans work but there is no video. I doesnt even look like its sending a signal to the monitor. What havent I checked? Or what could it be?

[ski]

Did the computers from which this one is built all work? If not, then you can suspect a bad MB, CPU, memory, or video card.
Do you hear any beeps?

[Superslinky]

I actually was just about to look the beep codes up. I don't even get a single beep. The computers that these parts came from had some errors that could have been fixed by reformatting the hard drive and a couple misc things. I brought all three systems from my uncles house to mine and when I started to set them up, I wasn't getting anything. I just find it hard to beleive that all the MB's and CPU's are bad. I think that my problem has something to do with something I did rather than parts being bad. Is there any special steps I need to take if I remove the MB battery? Maybe that has something to do with it. And to describe my problem further about the monitor, you know how your monitor would look if the power cord was plugged in but not the other cable to the video? Thats what it looks like when the computer is on. There is power to the monitor just no signal to get to come on. Plus all the RAM, CPU's, MB's and video cards I have, one of them have to work.

[ski]

Connect just the power supply module, MB, CPU, and case speaker, and place the MB on a piece of cardboard. If you do not hear any beeps, then either the MB or CPU(or both) is bad. Swap out with components that are known to work.
If you hear beeps, install the memory. Same beeps? Memory is bad. Different beeps? Install the video card. Same beeps? The card is bad.

[todd]

superlinsky it sounds like you have the same problem I have except sometimes mine boots and when I turn it off it will not boot and I don't get any beeps.
one thing I tried was to diconnect everything except the 3.5 floppy, keyboard ,video and leave ram in and try to boot from bios and ram to rule out hdd and cdromm.

todd

[todd]

one thing I forgot to mention was to check to make sure your ram is seated correctly and that you have the right kind of the same size.
Try moving the ram into different slots. No ram , bad ram or incorrectly fitted ram can cause a pc not to boot.

todd