CW black screen problem

Hello, so my problem lies in something odd, first of all i must add that my PC was before capable of running this game flawlessly so i dont suspect the problem nothing to do with my rig. Second i did recently just reinstalled my system (windows 7, no problems in other applications). After the reinstall, i did use a copy of the game which was installed on the old system, so i didnt installed it fresh, i just left the copy on my second half of the HDD, run it, worked, played a lot of cws and was great no trouble at all. Then later on i dont know what happend, from what i know i didnt installed anything new, because most of the things i need i install right after the OS installation, so no new programs or so, have an AV symantec antivirus, i dont know if that can be a problem, but i had it back then and before this happend, so i doubt that got do to something with it. Lastly ill explain the situation whats happening, so then, i start the game (which is now normally installed and updated correctly as i saw everything went smoothly with the latest update), get on to log in screen, log in, select server, select channel, select room, and play something, doesnt matter what, itll do the same to all modes. The thing that the game does, is like my title said black screen, for 5-10secs, then the loading appears, or its other way around, loading screen appears then it goes black and goes back to loading again, from there on no problem, i play like i ever did. When the game ends, again goes the whole screen black, wait a few secs, usualy around 20 or so, i didnt count sorry, then im back to in results screen and push ok, but then i usualy find out, theyll playing another game already, so yeeah maybe it took more then 20 secs. But im getting to my point, the worst thing about this is when i want to play a clan war with my clan, the first half is ok, but yeah u guessed it right, the second half is no go for me, and thats because of this black screen thing which takes too long to switch to results and then back to room, by then i can only push join, then disconnect and then windows 7. Its frustrating this, i didnt have this problem before, and i installed lots of stuff on my rig, and i didnt have nay problems, now that i didnt installed anything really, at least that way id get a quick answer whats the culprit here, but no, it must be something what i didnt thinkk of, but sadly i dont know what that might be, i hope that u know something what should help, and pls no system restore i didnt use this method ever, and was ok always, i wont use it now, and also i cant cause i switch of this thing, have a no big HDD and need the room, only 320gb, but its enough, but not quite enough for everything, anyway, pls help if there is a help, the problem started i dont know, like 2-3 weeks back, or maybe less could not quite remember. I only know that, thats when i decided to install the game normally and better use this, not the copy paste version.
Myspecs in short: E6600 2.4ghz, GF8800GTS 640MB, 2GB RAM, 320GB HDD, i think thats whats relevant, if u need anything else ill put it here, ty