I have the same onboard NIC and I have a similar problem although maybe it's different enough to justify another thread. Every time I upgrade to 6.10.x (I've tried all 3 releases) I get the "eth0 not found" message and the "e1000e: probe of 0000:00:19.0 failed with error -3" message in the syslog. Reverting to 6.9.2 fixes it. Messing with virtualization or the tg3 file doesn't have a lasting effect. I have had a handful of times it suddenly worked only to break again on a simple reboot (without making any more changes). The only way I've been able to fix it consistently/permanently has been to downgrade to 6.9.2.