Each motherboard has its own limitations but for instance an ASUS X99 Deluxe has two SATA3 controllers . The Controller 1 has 6 ports (SATA6G_1-6) which can be set for RAID and Controller 2 has (SATA6G_7-10) cannot be set to RAID. So you have to carefully study the manual for the specific board. Also now you have several new storage options SATA Express and with this motherboard, Dual PCIe 3.0 x4 M.2 Support which further complicates your options or the devices to connect to them.
If you are going x99 and want 64 GB RAM, I still have yet to find an available source for the 8 x 8GB DDR4 memory at any speed or any price!!!! For instance Corsair advertises the CMD64GX3M8A2400C10 for only $1010 but it is currentl out of stock and more importantly it is 1.65 volt where most DDR4 RAM is typically 1.2 volt.
thanks Bill !!.....a very helpful answer !!....by the way....I think there is a RAID option....if desired...in "our" G750JW s....I see it in the BIOS screen and know the "expensive" version offers it....not sure if it applies to OUR machines, or, it it would benefit in any way.
I have seen the RAID option in our G750JW but unless you have three disk drives, one for the OS/Application and two SATA III more for the RAID it becomes less usable. It could be done if you installed a drive/SSD in the optical bay and then you had the OS/Applications on it but then you could never take advantage of using the internal optical drive. I opted not to go that route, not even for a benchmarking run. I do have an optical bay drive carrier that I experimented with that now is unused