have you tried verifying your tf2/defragging/updating your drivers/deleting your excess folders/reinstalling?

right-click team fortress 2 on steam and go into properties and then into the 'local files' tab and verify your game cache

there's probably a better guide than this now, but this is what i used for defragging GCF files:
http://www.youtube.com/watch?v=ccmoToUgEpo

when you go into your 'tf' folder, back up everything that you actually need (config/hitsound/maps/whatever) and go back to 'steam\steamapps\*YOURSTEAMNAME*' and delete the 'Team Fortress 2' folder, and then relaunch the game

replace all your stuff

or just outright uninstall tf2 through steam and reinstall it completely

honestly i would try updating your drivers first though, because it's really weird that it just crashes to desktop with no error message or anything

edit:
i did a quick look through google and saw this thread, although i didn't read into it
http://forums-beta.steampowered.com/forums/showthread.php?t=3033187

sounds like it might be the same problem you're having though

also the other search results said that it might be a hardware problem as well, but you should check everything else first

thanks i will look into it.

atleast i know it is not my hud as your steampowered link says, i have tried multiple huds and also stock with the same result.

i defragged and verified the game, if it doesnt work ill try deleting my tf folder

I have the same thing happening. crashes to desktop without warning, the game sometimes still runs in the background but if i alt-tab back in i can hear everything going on in game but my monitor is black - no video.

It happens when i make an awesome play and kill a bunch of people or clutch a backcap ftw. its like i did too good and the game is mad at me

http://www.youtube.com/watch?v=YwoM3WqGiwQ

do that, should fix it.

tried this, havent crashed as of yet

There was a problem some of my friends had a while ago with setting -dxlevel to 81 in launch options which would cause them to crash like that. Try setting it to 95 or 90, if you haven't already.

also need help with this, verified multiple times, did #5 but still crashing. -dxlevel not in launch options either. :>

bumping for possible fix, constant crashing.

Hello sir, Just a friendly gamer here.

I may have a possible fix, i had a chat with Steam Support and they resolved my issue.

Please restart your computer and then follow these instructions to refresh your Steam files: https://support.steampowered.com/kb_article.php?ref=3134-TIAL-4638 /r/n Once completed, please verify the game's files: https://support.steampowered.com/kb_article.php?ref=2037-QEUH-3335

-Frost

This was happening to me. Clean out your computer of dust. Pay 50 cents for a slim paint brush and (with the PC turned off) remove all dust from your heatsink (on the CPU) and GPU fans/pipes.
Also my mate had a similar problem as well and he disabled his anti-virus when he laucned tf2 and it fixed it.

ive solved that issue thats making me mad

looks a problem with mcafee and his protection, just when you go to play tf2 or another game swith off the on-time protection into the mcafee interface

cheers