Hi all, I recently purchased parts for my first pc build. My last computer was a 200 dollar laptop and foolishly I bought current gen games like crisis 3 and far cry 3 thinking I could run them. Let's just say I made the most out of the 2 fps I had. Enough of that though. The problem I've been having is whenever I try to play a really high demanding game, it will work great for a while and then suddenly a screen with black vertical lines will pop up and the color in between the lines will depend on what was in the game at that time. I am running all of my games at ultra and have had the most problems with crysis 3. After a few days I was fed up with this so I decided to google it. I saw someone said to underclock with sapphire TRIXX so I did so and lowered the gpu clock to 1000 MHz. I was able to play for about three hours and then it crashed again. This also happens on a few other games. After it happens I can still hear audio, but buttons do not work and I have to hard reset. Another question I have is if I should crossfire because I have saved up enough cash for Christmas to get another. Would this be a smart investment? Will it help fix this problem? Finally and I know this is off topic but my hard drive is making a weird thumping/popping noise kind of like popcorn. I will most likely get a new hard drive because I am running out of space and because it is the loudest thing in my pc. Any help is appreciated. Thanks.