On my g300nh I was getting horrid results on writes with time dd tests, around 8 MB/sec.
I found a tweak that helped it go to 19 MB/sec after looking at some linux forums.
You can add this line to /etc/sysctl.conf and reboot or run sysctl -p.
/sys/block/sda/device/max_sectors=1024
or if you prefer to put it in a startup script or run it one time.
echo 1024 > /sys/block/sda/device/max_sectors
(Last edited by robnitro on 11 Feb 2011, 00:43)