Windows 7 Professional
AMD FX-8350
AMD Radeon R9 270x
For about a month now, my computer has been having extreme lag spikes. My speedtest will go from 30 ping and 20 mbps download speed to about 350 ping and 2 mbps download speed. The spike lasts anywhere from a minute to 30 minutes. I usually notice it when I'm gaming, as it severely impedes anything online, but I also notice it when I'm on streaming services. It happens across devices. It is not a problem with the modem because I recently replaced the modem and the issue persisted. I have run many MSE, Malwarebytes, and Adwcleaner scans and there is nothing. I have tried calling my ISP (Centurylink) and they say there is no issue. Any advice or ideas would be greatly appreciated. It's extremely frustrating not being able to play online games because of the risk of my high ping screwing over any teammates.
Another issue I am having, which may or may not be related, is a csrss.exe program having I/O reads in the millions. The number only increases, however, when I move my mouse. Otherwise, it is static.

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