I'm running a E8400, GTX260 core 216, 4GB of RAM.

I've effectively eliminated my GPU as the cause of the slowdowns :
 
Max detail screenshot : ~40 FPS.
Min detail screenshot : ~40 FPS.

As you can see the game isn't anywhere near GPU dependent on my system, at least.  Min details or max details makes no difference in framerate!
 
I've disabled many background processes including antivirus in testing.  I've tried multicore optimization in TF2 both on and off.  I've tried different settings in my BIOS.  TF2 seems to be the only game with disproportionately bad performance (while other Source engine games like L4D2 may not perform perfectly, they perform better than a busy TF2 server).

So basically my question is, should I expect frequent drops to around ~50fps in action and ~30fps in heavy action on this CPU?  Does anyone have a worse CPU that definitely gets better performance (I see a lot of people claiming this on other forums, but few reliable responses)?

That's weird. When did this happen? I would try it myself but I don't have TF2 installed on this PC at the moment.

I have never had issues with TF2 my new computer (Windows 7 GTX260 - Corei7-12gb ddr3) has no issues and it runs great and my last computer (8800gt Q6600 4gb ddr2) ran it perfectly as well it doesn't take a beast system to run the game so you should be running smoothly with no problems unless that E8400 is just screwing it up that much but who knows I would have to put my hands on it to get even an idea.

I wouldnt go as far as to say there is something wrong, but that seems a bit off to me. I mean, I probably average 65-50 fps..sometimes it may dip a little under, and Im running on 1920x1200 with custom console settings to get ultra quality and X8 AA. I have a GTX280GB, and 3.3dual core(dunno the exact name) with 4 gigz of ram and it is just fine.

@Diamond: I'm really baffled over this. Apart from emailing Steam about it I can't think of any other reason to fix ito or why it's even like that. You haven't overclocked your PC at all have you? I know some games just disagree with overclocking so if you do then it may be a good idea to set your PC to factory settings and see if that works. That aside, I don't have much to offer, sorry.

I have the same GPU as you and the fps numbers that you are describing sounds like the numbers i get.
I just have assumed that these are normal numbers for my card...

I have the same GPU as you and the fps numbers that you are describing sounds like the numbers i get. I just have assumed that these are normal numbers for my card...

You could try rolling back on a driver if you haven't done that actually. Sorry I didn't mention that earlier.

You could try rolling back on a driver if you haven't done that actually. Sorry I didn't mention that earlier.

Have you tried allocating a higher amount of the CPU to TF2?
 
Also maybe run the Net_graph 1/2 in game and see if there's anything with the connection when the FPS drop happens, could be the servers.

Tried setting higher CPU priority and tried turning down sound quality (just in case), no dice.  Here's some more screenshots I took with netgraph 2 on, looks pretty normal I guess.
 
Screen 1  -  36 FPS
Screen 2  -  also 36 FPS
Screen 3
Screen 4
 
I think I'm about done trying to deal with this shit.

I had the same type of problem on my old computer. No matter the detail level or resolution, I would always get ~30 fps when not in action, ~25 fps with a few dudes on screen, and ~15-20 fps in heavy action. The few times I tried to look into it, I always found people with the same problems as me, and computers leaps ahead of mine, that had the same types of drops. So I just left it alone.
 
 
 
My new computer that I built last month, however, runs it maxed out with no performance drops. So I don't know.

" @SeriouslyNow: Tried disabling all Avast processes, maybe some improvement but not much.
 
@Geno: I've known it wasn't GPU limited from my very first post in this thread, but I've heard a lot of claims by people with worse CPUs getting 60fps constant.  That's kind of the whole question.  There are a LOT of people that claim to get 100 or even 200+ FPS in Team Fortress 2 on my CPU or worse. "

" @Geno:
Makes you wonder how much of the rendering is actually happening on the CPU. Likely it's the bone animations and projectile physics. I just TF2'd a 32man server right now @ 1080p with vsync enabled (to push as hard as I could without FSAA) while I did get frame drops down to 35fps at the lowest points when it was really busy, I always started at 60 and mostly ran at around 40-50f/s.
@Geno:
@Diamond:
 
I found this interesting TF2 thread at Steamforums.  It includes a multicore benchmark recorded demo.  Why don't we all give it a go @ 1080 and see how we compare? "

Trying to find a driver that worked OK with Star Trek Online (not that I really want to play it that much but I'd rather have a driver that doesn't have major faults).  Well now STO is back to correct bloom but I'm having another problem.
 
Seems I'm having trouble forcing super sampling in Half Life 2 like I used to.  I've tried all sorts of stuff with the Nvidia profiles (I use nhancer to manage them).  I feel like saying screw it and going back to the latest WHQL drivers but Nvidia's driver section is down on their website.
 
AAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH

@Diamond:  Dude! Chillax :)  All your drivers which you've already installed sit in the C:\Nvidia folder.  No need to redownload them. :)

lag? 
 
seriously, i get that amount of frames at 1920 1200 on my imac  
so that can't be good

Yeah.  Geno may have a point though about your CPU because TF2 does indeed use multicore for rendering and calculating physics.  
 
Here's an idea : In the Nvidia Control Panel go to Manage 3D Settings and disable "Threaded optimization".  Doing this should prevent your GTX 260 from using CPU cores and clock cycle portion when the scenes get busy.  Maybe that will ease some of the load on your CPU.

Whoa those readings are crazy low. I'm running a Q6600 (G0 at stock), 2 GB DDR2 ram, and a 9800GX2 on XP and I get like 70 FPS (lower bound) and like 250 FPS (upper bound) in TF2 with EVERYTHING maxed out (including AA and AF).

Try this:   
  
http://forums.steampowered.com/forums/showthread.php?t=1093560

" @SeriouslyNow: Hmmm interesting idea actually, I will try that.  edit - tested it, ~40% LESS FPS on average, but an interesting idea to try. "

• My machine wouldn't successfully sleep/hibernate.
• Various applications and games would crash and Windows started feeling slower overall
• I checked my task manager and found that my RAM was all but eaten up.