I have an older desktop computer, and my son pulled the monitor connection out of the back of the tower. I had a person "fix" this for me by installing a different port/card. Before this the computer worked fine. After the new card was installed the computer worked for about an hour. Now when I try to turn it on it will come on, start loading, then shuts down. The monitor light stays on, and the tower light stays on but the tower itself doesn't run. At other times it doesn't even begin to load and simply shuts off (the light on the tower is still blinking) or will let me get to the login page then turns off. I'm pretty sure this has to do with the card, since it worked 100% fine before, & I contacted the person who "fixed" it but they now want to charge me to fix the problem they created. This computer has all of my school, business, and family info on it, ad I desperately need it working again. If you can be f help or have an extra video card laying around please comment or text/call 406-351-2469 (Anna). If I don't answer please leave a message & I'll get back to you.

Revised my post cause I had video card on the brain, chances are it's something with your motherboard. Did the person just fix the ports or slap a new one in there? If the first I can't be much help as I wouldn't begin to know where to start trouble shooting. If the second, than it may just be an issue with installation, or just a DOA factory motherboard. If it was plugged into the video card and he did something there it may be along similiar lines. Pictures and more details would be needed to make a good swing at what the problem is. I wouldn't stress to much your data is most likely fine on the hard drive.

[This message has been edited by Garrett Stein (10/3/2013)]

Thought I should clarify...
No Tim, the one you put in was great, but then it stopped working last week & a guy out of Billigs replaced the one you put in. His is the one that isn't working. But I had lost your number, so I'll definitely be giving you a call this evening to see if you can give me a hand, as I need back on this computer so I can get paid on Monday...

See if you can boot to safe mode. Restart the machine and keep pressing the F8 key until you are asked to boot in safe mode. See if the machine runs in Safe Mode with Networking and let us know the result.

It rarely boots long enough to do so, but when it did it only worked in safe mode (without networking) for a short while. Tim put a new card in this for me last year and it worked great, but when the card got replaced last week (not by Tim) it stopped working. I do have some computer troubleshooting skills, so if there's a chance this is settings etc I can try any suggestions if I can get it to boot up in Safe mode again. I will try starting it again shortly & update with what it does/says

Actually-- it sounds like a power issue to the motherboard (random losses of power). Could be 1) motherboard was irreparably damaged when the video port was damaged and now there's a power glitch/loose circuit causing power issues (or possibly damaged during this "new" installation), or 2) the new video card is causing a power drain/usage issue, or is improperly seated, damaged, etc.

Like Garrett above stated, your data is most likely completely safe on the hard drive and can be easily extracted.

I greatly doubt much software troubleshooting will help you with this issue; sounds hardware to me.

What are your specs for a video card?

Video cards can be quite power hungry. It's possible the new video card is more than your existing power supply can handle, or your power supply has failed.

Here's one example of a computer power supply:

My guess would be the new card is trying to draw too much power from the PSU, and/or the card has a PCI-E Power Plug that has not been plugged in and could be not providing enough power. Then again, it also could be a short in your motherboard from the original issue. All sorts of possibilities.

The best question to ask, as you did, is "What changed between it working and not working?".

KorysMama wrote:

After the new card was installed the computer worked for about an hour.

I would suggest either a bad video card (I've got 2 faulty ones that will either kill the boot up process or cause a BSOD shortly after),
or as mentioned above, a damaged motherboard or some sort of power supply issue (since some video cards require a massive amount of juice).

My 2 cents anyway, even though already mentioned.