Recently, since maybe a week ago I have experienced major frame drops in all games (e.g. Dota 2, Rocket League, GTA V, CS:GO). I could have a smooth 120fps experience on Dota, which would drop down into the low 30s' and 20s' for maybe 15 seconds, at 20 second intervals. I have not changed any hardware, nor have I moved it's location since the start of these frame drops. I have cleared my PC for dust with air and have run anti-malware scans.
My PC specs are as follows:
Processor AMD FX(tm)-8350 Eight-Core Processor
Video Card NVIDIA GeForce GTX 970
RAM 16 GB (DDR3)
Operating System Microsoft Windows 7 Home Premium Edition Service Pack 1, 64-bit