You said it's getting slow recently, have you cleaned it out recently to blow dust out of the pc? Have you tried using amd overdrive to monitor cpu temps (thermal margin, overdrive show how many degrees until throttling point reached rather than running temp). The motherboard isn't the greatest for an 8 core fx like the 8350, it's only a 4+1 power phase board and the vrm don't have heatsinks so more prone to overheating while trying to power that cpu.
Are you using the standard/stock cooler or an aftermarket cooler? Stock coolers or coolers that blow down against the motherboard are important especially for vrm that have no heatsinks. Something like a 212evo or liquid cooler that don't blow across the vrm can make the problem worse...