Updated Marvell raid controller (9128) with support for SATA 6Gbps RAID
No optional fan
Fewer heatpipes
No onboard reset button (onboard power button remains)
Single LAN port
P6X58D Premium:
Older Marvell raid controller
Optional fan
More heatpipes
Onboard power and reset buttons
Dual LAN ports
IMO the E revision is the best value in its price range (although Gigabyte has some USB 3.0/SATA III offerings in the same range).
I went the other way round. Just ordered the 'E'. I'm not a big OC-er but will give it a go hitting 4GHz with my 930. Will report back as I have more progress.
Oh, forgot to mention I'm coming from a P55 i7 860 so looking forward to playing with a i7 9XX. ; ))