Just over a week ago I was playing a game when my screen suddenly spazzed out. It turned into an image of vertical brown lines interspersed with a darker color line. The sound was skipping rapidly, as well. No keyboard commands worked, so I did the only thing I could—held the power button to shut it off.
When I restarted I received a black screen. The monitor was on and everything was the same as it was before, just no images on screen. The computer didn't act like it fully booted up, either. The fans were running, but as I said, no picture. The monitor's power button was flashing slowly, like it was in standby mode or asleep. I restarted several times (again, holding the power button) but it always restarted to the same result. I turned off the computer and monitor, unplugged the latter from the graphics card, and plugged it into the on-board VGA graphics. I started it up and got the same result, at first, but after then powering off and removing the graphics card, it booted up normally.
So I concluded, possibly incorrectly, that the problem was the graphics card itself. I cleaned and reapplied thermal grease to the heat sink in an attempt to solve the problem, but it didn't (it was a shot in the dark, anyway). So I ended up purchasing a new graphics card. After it arrived I immediately installed it, but I have run into the same problem—I plug everything in and up and when I power on the computer, I get a blank, black screen. As such, I can't go through the process of even trying to install drivers. I have disabled the on-board graphics through the Device Manager, but it didn't help. I've disconnected everything from the tower and removed the new card, then replaced everything, but there was no change.
After searching the Internet and wracking my brain over the possible problem, I can't determine if the motherboard's PCI-E slot has gone bad, or if the graphics card is defective, or if it's a problem with the BIOS, if the card is simply not compatible with my configuration, etc. Even though I can replace hardware and software and such, I'm not savvy enough with computers to determine such problems.
I do not have another computer system to plug the graphics card into and determine if that's the issue. I don't have an extra monitor to determine if that could be a problem, either.
This is my PC: https://support.hp.com/us-en/product/HP-Pavilion-p7-1200-Desktop-PC-series/5187022/model/5192622
Note: Everything about my computer is STOCK with the exception of the power supply, which was upgraded to a Corsair HX650W to be capable of supporting the older (dead?) graphics card. I bought the computer 5 years ago, so it's older than that (which may contribute to the problem).
This is the motherboard: https://support.hp.com/us-en/product/hp-pavilion-p7-1200-desktop-pc-series/5187022/model/5192622/document/c02980014
This is the new graphics card: https://www.newegg.com/Product/Product.aspx?Item=N82E16814202288 (most of this may as well be in Greek).
Another note: I'd noticed my computer running “harder”, the fans running more like maybe something was getting overheated, in the month or more prior to the old card going out. I'd opened the case and thoroughly blew out quite a bit of dust. I'm unsure if this has any bearing on the current problem at all, but I thought I'd mention it.
I admittedly did not do enough research or checking to see if the new hardware would be compatible with the old, as I know some things but not nearly enough. But if anybody with more knowledge than me can throw me a bone and help me figure out what exactly is going on, I would be very appreciative.