ASRock has a Work Station class board for Haswell-E with five PCIe 3.0 slots, support for up to 128GB of RAM which can be ECC if you install an appropriate processor and on the back are four of both USB 2.0 and 3.0 ports, one eSATA ports, audio and a pair of LAN ports.  They also included A-Tuning overclocking software which seems odd for a Work Station but proved to be very important as [H]ard|OCP could not get the system they built with this board to POST at default settings and had to change UEFI settings to get it to boot.  Once it did start up the performance was solid and it was one of the better ASRock boards that [H] has reviewed though with a street price over $300 it is hard to recommend.

"ASRock comes to us with its "Work Station" version Haswell-E motherboard. This time our out-of-box experience with its X99 WS was as rock solid as it could be and did leave us with feelings of getting to work with a quality component. As you all know, we are much more interested in how it performs at high clocks while under stress."

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