Yeah I'm pretty sure my onboard 10G Marvell AQtion ethernet is the source of most of my stability woes. About half the time any of these machines boot up, Windows bluescreens within the first couple minutes, and I think it has something to do with the iSCSI service crashing. Never had trouble in the old house where the machines had 1G network -- but load times were painful.
Luckily if the machines don't crash in the first couple minutes, then they settle down and work fine...
Yeah I could get higher-quality 10G cards and put them in all the machines but they seem expensive...