I recently formatted my hard drive and re-installed Windows 2000 + Service Pack 4 from scratch. I took great care in making sure every last setting and driver installation was correct.
As far as I can remember, I've been having this problem since I finished the installation, so I'm pretty sure that it's not from spyware or viruses. I recently did some scans anyways, and it didn't help.
Whenever I start up a game of mine called Worms Armageddon, just a few seconds after it switches to full-screen, my connection drops.
As far as I know, the game does not try to send or recieve any information on startup, as it just goes to the main menu.
A few seconds after this happens, the modem light flickers back on, as the connection software is set to automatically re-establish the connection if it drops.
After the connection is re-established, I am able to log into the game's online lobby. The connection then stays until a match is started. When that happens, the resolution changes, the game loads, and the connection drops/reestablishes again. The connection also drops whenever I exit a match back into the lobby, minimize the game, or quit the game completely.
I am not always able to continue after the modem light comes back on. Half of the time, I have to quit the game, exit the connection software, and start from scratch.
I have no other connection problems besides this. All of my browsing and file-sharing works fine.
My specs are:
ISP: MTS Allstream
Modem: Efficient Networks Speedstream 5200
Connection: ADSL via PPPoE @ 1.5 mbps downstream, 384 kbps upstream
Connection software: Efficient Networks Enternet 300 version 1.5c
CPU: Athlon XP 3200+ Barton Core @ 2.2 GHZ, never overclocked
RAM: 1GB Kingston HyperX DDR, never overclocked
Video card: XFX 6600GT
Motherboard: Asus A7N8X-E with nForce2 chipset
LAN: Onboard 10/100 Nvidia port
I built my computer myself, and I can assure you that all the connections are secure, all the BIOS settings are correct, and that the power supply and cooling are sufficient.