On 08/20/2010 12:15 AM, Timo Schoeler wrote: > 0d:00.0 Ethernet controller: Intel Corporation 82573E Gigabit Ethernet > Controller (Copper) (rev 03) http://download.intel.com/design/network/specupdt/82573.pdf 17 ASPM/Jumbo Frames Disabled Due to Early Receive Threshold Overrun Buffer Status: Intel does not plan to resolve this erratum in the 82573 Gigabit Ethernet Controller. Jumbo frames is not supported in 82573E/V & is supported with the workaround above in 82573L. You'll have to use different hardware. The chipset you've got has a bug, and jumbo frame support is disabled as a result.