I'm having a massive problem with my internet at the moment and unfortunately for my flatmate I seem to have tracked it to his brand new desktop PC. Earlier tonight as soon as the wire for his PC was plugged in the internet ground to a halt. The Router, which had been getting a 1.6Mbps downstream all day (yeah our internet sucks. We need to get it changed) suddenly disconnected and when we restarted the router it was down and 0.6Kbps. Sounds like something on the ISP end, I know, but it is definitely to do with his computer. Eventually the computers just wouldn't connect to any site but for some reason Skype worked just fine. Installed Wireshark on his computer and took a couple of log files (I can upload if you would like). The first highlighted an IP checksum problem, we went into the system and disabled all IP checksum offloads and the 2nd log showed no black entries. Now its back working again but not very quickly. When his computer wasn't plugged in I got a 1.5Mbps SpeedTest.net downstream, now its 0.25Mbps. I'm no network guy so any ideas what the hell could be going on. Near as I can tell its not a "Packet Storm" (something I've heard off that can ground networks to a halt) as there's no constant repeating packets in the logs.