It's not that the SM951 is entirely out of the picture, so much as I'm thinking of holding out for NVMe. The SM951 NVMe should be released soon (as in any day now) although they'll probably be in short supply initially, which means they'll sell for a premium. I'm also not entirely sure that booting Windows 7 on a Samsung SM951 is a sure thing. I may have to jump through some hoops to make that happen. I have read in multiple forums that the only way to get Windows to boot on an SM951 is by installing Windows through a USB flash drive. Any other way, to include cloning, will not work. I have more questions than answers in that arena.
My other consideration is that if I go with the ASUS A97-PRO WiFi, then I only get a PCIe 2-lane solution on the M.2 socket. To take full advantage of a PCIe 4-lane SSD on that motherboard, I'll have to go with an adapter. Or I could just run the SM951 on 2 lanes and still get better performance than SATA. I consider just waiting for the technology to mature and then go with a PCIe adapter solution. Then I'll tell myself that I should have gone straight to a Z99 motherboard and a 40-lane CPU.
As for the Noctua, I'm looking at the higher performing cooler is all. I still need some time to look over those options. For that matter, I remain flexible on whatever I haven't purchased. I'm strongly leaning toward the ASUS A97-PRO, but I continue looking hard at the Extreme6. I can still be swayed on the SSD, and I may go for a larger PSU if I catch a good sale. There's still the GPU option as well.
One other fudge factor is that I will have to purchase new copies of Windows. My current computers will go to 2 of my kids, which means the Windows licenses will stay with those builds. So should I buy Windows 7 and possibly upgrade to Windows 10? Should I buy Windows 8.1 to ensure a boot installation on an SM951, and then upgrade to Windows 10? Should I go straight to Windows 10, which I haven't even tried yet and hope it boots on an SM951?
Here's a great Tom's Hardware article on the
Samsung SM951-NVMe Versus AHCI Versus SATA 850 Pro. The article reminds users that NVMe will only work if the motherboard firmware supports it. From the article, "If your board vendor of choice isn't deliberately adding NVMe support, you won't be booting to an NVMe drive any time soon." I have no idea where the ASUS Z97-PRO is on NVMe support.
This Tom's Hardware forum topic is also timely. The person who replied (JohnnyLucky) has built a fantastic database on SSD reviews, and he makes good points on warranty & support on the SM951. He also points out possible heat issues with M.2:
Samsung 850 Pro or Samsung SM951 on Asus Z97-ProScuzzy; I am so confused.