First of all, hi
I've a problem
I have a single wired connection that I use separately on my desktop and my laptop
Of course ip and dns settings are the same on both
So same settings , same connection and same windows xp
Here is the thing, I work most of the time on the laptop
After a while the connection stops receiving packets
In a few times I can make it work again by unplugging & plugging it in a certain way, but mostly I fail to work it out
Then I plug the cable into the desktop, and it works perfectly
Back to the laptop, still no packets received
Its msi with realtek network adapter which is probably the same network adapter in the desktop
I'm suspecting the problem is with the network card, maybe it needs a windows reinstall
Note that the connection works fine at the first hours then it goes down after a half day

Not knowing what is upstream makes this harder. Static IPs may be an issue. Some switches and routers may have a problem with the same IP showing up with different MAC addresses for security reasons. If your network supports DHCP you should give it a try it may solve your problem.