Hello and thanks for the help. My parent's pc wasnt working so I took a look at it. I noticed the chipset fan wasnt working and took it to a repair shop. They SAID that that wasnt the problem, the CPU was well-ventilated and most likely that chipset wasnt working for a while and the problem was not hardware because they tested it/ According to them, is a SOFTWARE problem and wanted me to PAY $85+tax, which I don't have.
So here's the symptoms: when I press the power button, the lights come on, fans starts and I hear all the familiar noises BUT nothing shows on the monitor.
One thing I've noticed, whenever it DOES work, it emits a beep right after it turns on and everything goes well. I DO NOT hear that beep when it doesnt work.
When it DOES work (beep is heard) and windows load, it crashes a few moments after loading desktop and icons, etc.
Yesterday it did boot and I went to SAFE MODE to try and get all the data and it never crashed! So I think it's probably something on startup that's causing it to crash, right?
So I've read somewhere to make a AVG boot disk and I've done and tried and switched the boot order to CD/DVD 1st. It was working and then got stuck at some point and I just restarted it but I just get black SCREEN now and NO beep.
Motherboard model is MSI MS-7125, OS is Windows 7.
Let me know what else is needed.
THANK YOU SO MUCH for your time. It is highly appreciated.

Re-seat RAM and all add-on cards.How do I do that?
Thanks

Oh, just a quick update.. I was running it normally now (even turned it on and off 3 times) and ran an anti virus and nothing was found. I restarted it to see if it would work again and nothing. Just the black screen and NO beep. It's LIKE random..