I have a desktop with and AMD fx-6200 processor, 10gb ram, 128 GB SSD, 1.5 tb 7200 rpm hard drive, AMD Radeon HD7570 GPU. The computer has been great up until last night. It is fine on startup and reboot but after about 5-10min of running it slows to a crawl. At first i thought virus or malware but a ran full scan with both AVG and AdAWRE SE and no problems were found. I also tried PCPitstop and it came through without any problems. All pcpitstop tests passed with flying colors and rated pc in the top 14%. All this while it take about 2 minutes to open internet explorer. I can right click on the screen and about 45 seconds later the options box pops up. It takes 3 minutes open up control panel and for everything to appear on screen. It is just ridiculously slow out of no where. I don't know where to start. Also should note its a windows 8 system, no bloarware, cpu usage is at 20% and memory usage is at 13% while this is going on.I have 40GB free on the SSD and 1.1TB free on the HDD. While this going on if i do a reset it will boot in around 15 seconds and be fine for a few minutes then the problem starts again. I tried to do a system restore to an earlier point but it seems as though in my infinite wisdom I never set one. Any ideas on diagnostic software or where to start would be greatly appreciated.