not sure if its on a splitter or not, but the other wireless pc doesnt have this problem.

i was more wondering if it was a spyware/malware type problem, but all scans reveal negative.

Try this...

if there is no splitter...
Update NIC card driver
Disable Nic Card
Restart Cable modem
Restart Wireless router
enable nic Card

see if connection works

if there is a splitter...
remover splitter and plug cable staight to modem, (they have been known for hang ups in internet)
Update NIC card driver
Disable Nic Card
Restart Cable modem
Restart Wireless router
enable nic Card

see if connection works

Im having this same kind of problem with my cable modem right now.. I have the same stuff as Sultan

linksys wireless G card
linksys WRT54GS router
cable internet.

I searched for updates for the NIC card but windows said It couldn't find any better than I have installed. I tried resetting everything but still didn't work. Everything worked fine before I installed xp pro.

Had the same problem before, and I think it?s caused by the build in firewall inside the router.
Because I checked the log file and indicates interruption exactly on the same time it disconnects so... I guess it must be that.

Try to fix it by turning the firewall (inside the router) off and use software firewall instead.

How do you turn that firewall off?

if u have the same router as me, log in to your settings, click on security, then firewall, and put the dot in disable. but mine is disabled, and i still have same problem.

i recently moved, and have a completly diferent isp/cablemodem and i still have that problem. only thing i havnt done is update the drivers for my wireless card, but as it worked fine before with these drivers, i believe the problem to lie elsewhere, may try updating drivers later if i get bored enough.