Wireless works, Wired connection doesn't

Hi, I'm at the end of my tether with this. I've had an ongoing problem for several weeks and am desperate for some help. I have a 4 Port/Wireless Router/ADSL modem. Connections via Wireless work fine. The wired connection from my PC doesn't work. It was working fine and then started to fail. When I first turn on the PC it initially connects to the Internet fine (we're talking a few minutes at most) and then rapidly slows down to a crawl before losing the connection altogether. Pinging the router is intermittent - sometimes successful, sometimes not. I can do some more scientific assessment of this if you want. Things I've tried: Spybot Search&Destroy Anti-virus scan Disabled onboard ethernet and installed a new PCI card in its place Replaced router Replaced cable WinsockXPfix Loads of other things that I've probably forgotten! All of these have failed to fix the problem so I'm guessing it's something in my configuration or a fault somewhere on the PC. The Log from ipconfig/all on the PC is as follows: Windows IP Configuration Host Name . . . . . . . . . . . . : simon Primary Dns Suffix . . . . . . . : Node Type . . . . . . . . . . . . : Unknown IP Routing Enabled. . . . . . . . : No WINS Proxy Enabled. . . . . . . . : No DNS Suffix Search List. . . . . . : lan Ethernet adapter Local Area Connection 2: Connection-specific DNS Suffix . : lan Description . . . . . . . . . . . : VIA Rhine III Fast Ethernet Adapter Physical Address. . . . . . . . . : 00-A1-B0-60-1E-DB Dhcp Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes IP Address. . . . . . . . . . . . : 192.168.1.65 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 192.168.1.254 DHCP Server . . . . . . . . . . . : 192.168.1.254 DNS Servers . . . . . . . . . . . : 192.168.1.254 Lease Obtained. . . . . . . . . . : 20 April 2010 16:27:37 Lease Expires . . . . . . . . . . : 21 April 2010 16:27:37 I can let you have a HijackThis log as well if that helps. Any assistance appreciated. cheers, Simon

Thought I'd add some extra information in case it could be of help. Other things that occur to me as possibly pertinent are that Carbonite stopped working a few weeks ago (don't think it's because it can't find the internet - seemed to get corrupted. Haven't re-installed yet because I don't see the point with no internet connection). I had a hard disk problem a few weeks ago that could have corrupted some stuff. Think it over-heated (rare as it is) and it ended up looking terminal before I let it cool and fixed the problem that had caused the overheat in the first place. The Hijack This log is as follows: 📎SimonJMHJTlog.txt Reason for edit: Remove HT log, only allowed in Malware forum.