Better is subjective. The AsRock is a very good board and has two Plex units that allow the full 16x bandwidth for 4 cards. And it does have a built in LSI raid card that is really sweet as a concept and one that makes it very attractive to me for a server board.
But here is the most damming of comments from a review site and reviewer who I personally know and trust.
Performance wise, the X79 Extreme11 does not win many accolades. It performs similarly or worse than other X79 motherboards in the market - in our GPU testing, the board continuously came near the bottom. The separation ASRock likes to make with the X79 Extreme11 is the PCIe functionality and the ability to include SAS drives on board - the speed of the extra ports reached a staggering 4.0 GBps, even though that may not be a realistic use scenario. The extra ports also are a little hampered by not having additional cache to help with writing short transfer sizes like on a PCIe card.
SouceThe board was giving a bronze award for innovation and I must stress that Anandtech does not hand these out like some other review sites.
That being said if you are not going to be using the board in the manner that Ian has highlighted then there is no point in getting one. A RIVE will out perform it day in and day out. As a top end board I am sure that build quality will be good. And regardless which you do go for in the end you will be happy I with your choice I am sure.
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