I did a little more research and here it is:
http://h20564.www2.hp.com/hpsc/doc/public/display?docId=c01722374
(This is a HP document about RAID setup with SAS or SATA drives, for your Z800)
http://h20564.www2.hp.com/hpsc/doc/public/display?docId=emr_na-c01840936
(The important point here is that a normal "clean" W7Pro64 install will not include the necessary LSI drivers. This same thing happens with a Z620 and its on-board TI USB3 chipset..... you have to know to add those in after the clean install or your USB3 ports won't work.
HP makes their clone image masters with the necessary added drivers included on that image. That is what the "Restore" image and media creation idea is all about. Such an install (from the HP Restore media) includes the necessary drivers and also the HP OEM COA license that is linked to your general HP workstation type. As such, this image can generally be cloned from one Z800 to another. Of interest, an image from an old version 1 Z600 would not clone over to a newer version 2 Z600, but one from a version 2 will clone over to another version 2 Z600. There is a hard coded identifier difference coming into play there.)
http://h20564.www2.hp.com/hpsc/doc/public/display?docId=emr_na-c02328795
(see #6 re Z800 down at the bottom, regarding moving the Blind Mate connectors from SATA ports to SAS ports (just below on the motherboard, the set of 8). In contrast, SATA ports are "0"-"5", for 6 total.)
http://h20564.www2.hp.com/hpsc/doc/public/display?docId=mmr_kc-0100529
(Zoom in on the top image, and it shows 4 Blind Mate connectors attached to the bottom SAS ports in this particular Z800.... the 6 SATA ports can be seen just above those cables, all empty. This is interesting.... the workstation appears to have come from the factory preconfigured with 4 SAS drives in the drive drawers, and HP is showing how you would connect those same SAS drives to a LSI PCIe card rather than to the built in LSI controller's SAS plugs on the motherboard. This implies that the SAS drives fit in those drive drawers just fine.)