Strange pc freezes but voice chat still works

[Mummi]

Hello, I've been having occasional times when the game/my pc freezes up completely, no response from keyboard or mouse, except I can still hear voice chat, and if it froze while I had pressed the push to talk key I can talk in voice chat.

It seems to have started after I switched my ISP to virgin cable 20Mb but I'm not sure if that is anything to do with it or not. Any help would be much appreciated.

[Mummi]

Thought I'd add details of my computer, tis self build

Asus P5B-E motherboard
Core 2 Duo E8600 3.3Ghz +Thermalright cooler + 120mm fan
2x 1GB corsair DDR2
Geforce 8800GTX with Thermalright HR-03 + 92mm fan
onboard soundmax audio
intel x25 M SSD 80GB
PC Power + Cooling 750 silencer PSU
Merc stealth keyboard
roccat kone mouse

Windows 7 home 64 bit

nvidia drivers 8.17.11.9745 03/04/2010
soundmax drivers 6.10.2.6520 10/07/2008

[donfilibuster]

Network hiccups happen and the exact kind of lag may vary but apparently your actions are still queued so make sure you are not adding more lag until the first slowdown or freeze ends.

For example, when you are fighting and get dps lag but keep attacking and manage to kill your monster 'in the blind'. Of course, if were about to jump then tough luck.

You also mention voice chat and well, chances are that adding voice on top of a busy system or network won't make it unstuck faster.
I have seen several people that go on to vent over voice chat when stuck and don't really recover until they are literally told to shut up and let the lag ease up.

[Mummi]

I really dont think it is network lag as it seems to be client side, the system stops responding and i have to use the restart button to reboot the pc.

[Mummi]

Well an update, I had a faulty usb device a keyboard which seemed to cause the problems, when the game froze windows was losing the keyboard usb connection, then finding it again.

Then the problem started reoccurring but more severe in that the system would crash. This was down to the graphics card overheating, which I've fixed now I think.

Now the issue has resurfaced, the black screen crash that I've read other people have been having too. I think I've sort of fixed it, although I'm not sure, by downclocking my graphics card, setting the vsync on and running medium details, need to test some more to see which of these fixed it or if all of them did.

Anyway now it looks like I'm potentially in the market for a new graphics card, which I'm not very happy about as I but nevermind. I'm looking for suggestions for cards or suggestions for ones to avoid. Thanks.