I've a Gigabyte G1.Sniper.M3 MB with 82597V chip and the connection drop problem as well. I tried different driver, settings, cables and switches without success. Bought a € 10,- TP-Link PCIe NIC with Realtek chipset and all problems are gone. But that’s not satisfying.
For me it's clearly a driver issue and I ask myself if it's the same issue as discussed for Linux here http://communities.intel.com/thread/26804?start=0&tstart=0
Some clever guys take a look at the source code and became aware that the 92579LM chip has "K1 power save" optimization and at 1Gb speed this is causing the chaos. Disabling the K1 power save optimization in a patched driver fixed the problem.
@Intel: the Linux solution dated June 2013, Intel's latest Windows driver dated May 2013. Is it possible to disable and test the „K1 power save" optimization for the Windows driver as well?
Ralph