I used to be able to play TF2 smoothly on high settings with no stuttering on multi-core mode. Now when I turn on multi-core I get frequent 'micro' stuttering, and when I turn it off I just get the regular less-frequent but more substantial stutters and poor framerate in heavy action.

I've turned all my settings to low, put on Directx 8 mode and run around 2fort on an empty server but I still get stuttering when multi-core is off, and frequent micro stuttering when multi-core is on.

I'm at my wits' end with this issue and Steam support haven't been very helpful. I manage to play Bad Company 2 fine.

I did all the standard tricks, updated my drivers, turned off steam cloud and deleted my local files, closed all background processes and antivirus, used an fps config, etc... nothing helps.

Asus P5KC mobo
Intel Pentium Dual Core E5200 2.5ghz (based on the core 2 duo, not the pentium D)
2gb Ram
Nvidia 9600GT 512mb
Windows 7 64 bit

TF2 is woefully optimised, and we're long past the time where the recommended settings are relevant.

So, let's start from scratch and try to get your game running smoothly, even if we have to make some concessions to graphical fidelity.

Looking at your specs the first thing that sticks out to me is that you're running 64bit Windows 7 but you only have 2gigs of RAM. If you don't have 4 gigs or more then you don't need 64bit, and if anything it will cripple your performance before you've even started the game.

Multicore in TF2 is a little wonky. It wasn't natively supported in the Orange Box engine, but Valve have patched in some code that makes it sorta kinda work. You're running a dual core processor @ 2.5ghz. TF2 is a CPU monster, and 2.5ghz is a little underpowered at this point (thanks to the woeful optimisation I mentioned previously). You could look into overclocking your processor (3.0ghz should be possible & would help a lot), but we'll consider this at a later point if needed.

Your GPU should still be fine for TF2. As I mentioned before, TF2 is more CPU dependent than GPU.

Remove any custom configs you might have, so if we run into any problems we can rule those out.

OK, do you use any launch options?

I've modified my own to suit your hardware, you could try adding them:

-noforcemspd -noforcemaccel -noforceparms -novid -windowed -noborder -console -heapsize 1024000 -noipx -nojoy -32bit -threads 2 -high -gl

There are a few more you could add depending upon your monitor resolution & refresh rate:

(width) -w 1920
(height) -h 1200
(refresh rate) -refresh 60

Try this with the recommended settings & let us know if your fps/stuttering issues continue.

It might be necessary to use a config, but we'll see about creating a custom one for you instead of something off the shelf.

Yeah I can add to this, with my 2.0ghz dual core 2GB Ram 32bit it took 5 Minutes from startup to join a server.

Thanks henchling, I'll give the overclocking and some of the launch commands a go.

However I really think there's something going on here other than a gradual decrease in optimization - after the Replay update and before the Free2Play update I could run it all fine at very high settings, with multi-core on, with no stuttering and a great framerate. The day the F2P update came out, I went on TF2 and it had all gone to hell - unusable multi-core and low fps even when my settings and directx level were at rock bottom. I know all the weapon models have no LOD reductions at range, but on a completely empty 2fort server I still get bad stuttering with low settings.

I'm reluctant to spend money on obselete DDR2 RAM (can't justify an upgrade to DDR3 at the moment, would need to replace mobo + cpu) when I'm reluctant to believe it's the issue. For general use and the other games I play, 2gb is just fine.

I would do the following as a first call:

turn off steam cloud for TF2
Delete (or move out) the team fortress 2 folder in steamapps/username/
Run a verify files on tf2 and defrag the gcf files. then set -autoconfig in launch properties Run TF2 and configure your basic options.. see how it performs.

Done all that already, as Steam support directed me to. Also updated all my directx stuff, graphics driver, Intel chipset driver etc, defragging my files with Defraggler. Nothing seems to make a difference.

tf2 is goddamn weird when it comes to specs. for me it ran smoothly on low-medium settings on a 3.2 p4 2gb ram and an old 7600 gt (having 28-10 fps constantly). then I went to my friend that has a six cored amd, and a direct x 11 ati card with 4 gigs of ram on a 64 win 7. he got 15 fps on some points of goldrush. and the top fps was 63. now that's just retarded.