If you were experiencing low FPS, stutter, or lag since the last update try this. I'm not saying it's an accurate fix, or makes sense. But it worked for me.
I tried every possible software solution. Verified cache, deleted/replaced drivers, reinstalled TF2, blah blah blah. Nothing worked. Hardware stress tests. Everything performed to specs.
I decided to take apart my box and reassemble. Not recommending this. But it fixed my issues. Essentially pull out your video card and re-seat it. While you're in there blow out all the dust and crap.
When I restarted my computer I popped into the bios and noticed the clock was off. The time didn't coincide with the time I had things disassembled. I adjusted. Launched, opened TF2, popped into a server, and had no more issues.
my ins and outs are still fucked. But no lag or stutter.
Before
http://steamcommunity.com/id/failhorse/ ... tab=public
After
coming soon.
Something else you can try if this does fail. Heard it worked as well. Open launch settings. Add +cl_forcepreload 1
Good luck. If you're having issues and try these solutions post results.