Running Windows XP on a small peer-to-peer network (3 computers), connected to a modem/router.
One of the computers network access intermittently slows down significantly.
This problem happens regularly but intermittently. When the problem happens, if other computers try and access it's files or vice-versa it is very slow or if it tries to print to a printer on another computer it is also very slow.
I put in another network card (different brand) and that made no difference.
I ran a continuous ping test to the router from this computer and most of the time it says <1ms or =1ms but sometimes it goes up to 10ms or more. The other computers on the network all show <1ms or =1ms. However, when the problem occurs and i ping the router it often says <1ms yet access is slow, so the higher than usual ping times don't always correspond to when the problem happens.
I ran the ping test in safe mode overnight and the highest reading was 2ms. When I ran it in normal mode overnight it was 10ms or more.
This lead me to think it was a software issue but I have looked at each process in task manager and there was nothing out of the ordinary.
It has up-to-date AVG anti-virus and I ran Spybot over it with no infections found. All service packs and updates installed.