I have a Marvell Yukon 88E8052 ethernet card which they support with an official driver called
On both Ubuntu 10.10 and 11.10 I get the following results on http://speedtest.net when using sk98lin:
120 Mbps down, 100 Mbps up
On 10.10 without sk98lin (just using the Ubuntu defaults) I get better results:
150 Mpbs down, 120 Mbps up
However, on 11.10 with the defaults I can't even load the speedtest.net website. Everything is incredibly slow. The best results I get when using apt-get (for example) are in the 50 kbps range, and that's after I've tweaked my MTU and messed around with a bunch of settings like disabling IPv6 and setting up DNS manually (without the tweaks it's more like 20 kbps). There are no dropped packets, it's just super slow. This leads me to believe it's a problem with the driver, though of course it might be something else.
How can I fix this? sk98lin is fine, but I'd like to figure out what's going on and hopefully be able to use 11.10 with the 10.10 speeds; that 30 Mbps boost over sk98lin is valuable when downloading large files!