if your other computers don't loose connectivity, try swapping the ethernet cables from one of them to your primary computer and see what happens. if your connection keeps dropping, there's obviously a problem with you computer. if you want to find out if it's a messed up setting in your windows env., trying booting in safe mode with networking and see if it's ok then. if it is, you'll just have to find a problem in windows. if not, there might be a hardware issue. well, there is a zillion things that could have gone wrong here, so i guess you'll just need to troubleshoot and eliminate every option one by one. you can also try removing your connection altogether and adding it back (in network connections). you can try adding/removing your TCP/IP connection, etc. etc..
2011 E92 M3 - IB/Beige/Sycamore Wood/6MT/EDC/ZPP2/Nav/PDC/Heated Seats/iPod-USB/Enh. Audio
2008 E92 335i - Montego Blue/Black/Gray Poplar/6MT/ZPP/ZSP/Nav/PDC/Heated Seats/HDRadio/iPod-USB - Sold
2006 E90 330i - Mystic Blue/Black/Aluminum/6MT/ZPP/iDrive/PDC/Heated Seats/Sat. Prep - Sold
1994 E36 325i - Boston Green/Beige/Automatic/ZPP/Heated Seats/Premium Sound - Sold