M.2 x4 vs SATA Express

[silk186]

Looking at a review of the ASRock Z97 Extreme6 it talks about the inclusion of an M.2 x4 slot and SATA Express. The way I understand it the M.2 can run off either SATA or PCIe?

I get the benefit in size for M.2 in laptops and other SFF enclose like intel NUC but what is the point of throwing one on the back or an ATX board? Why would I go with an M.2 drive over a SATA Express drive if space is not a concern?

 

[evilsofa]

From the wikipedia article for M.2:

"Essentially, the M.2 standard is a small form factor implementation of the SATA Express interface (which provides support for PCI Express 3.0 and Serial ATA 3.0), with the addition of an internal USB 3.0 interface."

 

[silk186]

I understand what it is, not so much why the M.2 standard is present on an ATX board. Does it have any advantages over SATA express.

 

[Lunas]

for cable management and making the setup clean.

 

[Dawizman]

The m.2 drives I have seen reviews for seem to be faster than the standard sata ssd's.