I'd bet that any SSD would work with your motherboard. Keep in mind that your board only has SATA 3.0 Gb/s which won't take full advantage of typical SSD speeds. The idea of using a PCIe card might be better because you'd have 8.0 Gb/s of bandwidth in a PCIe 2.0 x16. That said, you never really know if a PCIe card will work in a board until you try it. Don't buy an off-brand card. The worst problem might be reinstalling W-10 with its arcane licensing scheme.
I am using a SSD on my DP55KG system, so I can attest that they can certainly be used.
As paramountain indicated, the SATA ports on this motherboard are only 3 Gb/s. I used a PCIe x1 SATA controller card to get 6 Gb/s performance. If you do the same, be sure to choose a card that includes an Option ROM so that it is possible to boot from drive(s) connected to this card. The board I have didn't have an Option ROM, so I had to put together a hybrid Windows 7 configuration that booted from the (3 Gb/s) data HDD but used the (6Gb/s) SSD as the System drive (it also rooted the Users folder on the data HDD as well; see how in this Tutorial).
Regarding the second question, I have used a number of adapter cards that allow MSATA or M.2 SSDs to be connected to standard SATA or USB interfaces.
Gentlemen, Thanks for the responses!
I did purchase a PCIe board and an M.2 card. Even after updating the BIOS, the board refused to recognize the M.2 board at all. The thought of going through what Scott did just 'hurts my head'! So, for now I will leave things as they are and possibly, after Christmas, I will look into a complete overhaul with a new motherboard, etc.
I truly appreciate your replies!
Which PCIe card did you purchase? Because of the age of the motherboard, I believe that the card needs to be one that provides its own on-board SATA Host Controller (I see that there are a lot of M.2 to PCIe adapters out there but I don't believe that they will work). Also, when you are using a board with an Option ROM, the attached SSDs/HDDs don't necessarily show up in the BIOS' boot device display (i.e. the Option ROM provides a BIOS setup extension that you enter via a hot key and which you use to see/configure the attached drives).
In my case, I already had a cheap (cost me US$12) MSATA to SATA adapter that I bought for testing purposes. I connected my MSATA SSD to this adapter and first tested it connected directly to the motherboard. To increase performance, I later cabled it to a (more or less standard) PCIe SATA controller card and went from there.
You could purchase a similar M.2 to SATA adapter and do something similar to what I did. The M.2 versions are slightly more expensive than the MSATA versions (US$15 vs US$12). There are even some that put the M.2 card into a protective enclosure (final result looks just like a standard 2.5" SSD) for not much more money. Here's a (US$23) example that I found: Amazon.com: ZTC Sky 2.5" Enclosure M.2 (NGFF) SSD to SATA III Board Adapter. Multi Size Fit with High Speed 6.0GB/s. Mod…