Alright, so before going to the Nvidia beta driver, since I played NWN too much, I stuck it out. However, today, while using Goto Meeting, I noticed that the video and audio would stutter, or just stop periodically, just like TF2.
So, I went on Speedtest.net and did a few tests. Like every other test that I ran, the speed would be fast, and then all of sudden drop to 0, on both downloads and uploads. I ran a test on my iMac that is right next to my laptop and on the same network, and it was fast without missing a beat.
So, then I started looking at my wifi driver. I'm using a Broadcom 802.11n driver, published by Microsoft for Windows 8. Now, I know I didn't have these problems when on Windows 7. So I loaded up my Win 7 x64 driver (which looks to be the latest driver published by Broadcom, themselves), and these problems went away for me.
So, that was it for me. Try checking your network adaptor drivers, because the ones that were loaded with the install didn't work out for me.
I had the same problem as you I believe. Although I'm a noob I worked out my problem was with the network drivers.
while effortlesly looking for a w7 driver and trying to install it, I noticed I didn't have these problems playing games when I used my integrated GPU instead of my Nvidia driver... so this kinda baffled me, however none of the nvidia driver versions work for me (266.58 -too old-, 285,62 -crashes-, 295.73, 306.97, 310.70 -lagspikes-) I have Optimus with an integrated intel and nvidia geforce GT 425M
So im looking back to my network drivers; maybe there's something wrong between the nvidia & network drivers?
but I just can't seem to: a) find the right drivers b) uninstall the current drivers c) install the downloaded driver... im not a total nab, I have no problems with installing/uninstalling nvidia or other drivers. these are my drivers under the network adapter tab:
Qualcomm Atheros AR8131 PCI-E Gigabit Ethernet Controller (NDIS 6.30)
Realtek RTL8191SE Wireless LAN 802.11n PCI-E NIC
So Ill try finding a w7 driver for this Realtek driver?