I was impressed by this drive's numbers, but mostly by reviewers' comments that it started and ran programs as if they were cached in memory - my fast SATA3 SSD couldn't manage that. But there was little in reviews about boot times. Some feel like Intel was conspiring with review sites to not publish them, but one site (above - SSD Review) said originally they didn't see it as a negative because they believed it required additional enumeration during POST.
Here and elsewhere though I've seen comments that it's also slow during the Windows splash screen. One user watched the lights on his 750 during boot, and at one point which coincided with the moment at which the boot paused for a few seconds the lights were out. I wonder if the 750 has a more advanced POST that takes a little while, it does have an enterprise pedigree. If so I'd be less concerned.
It doesn't appear to be a BIOS issue as PCPer assumed; the NVMe 951 has no slowdown.
But either way (and although the 750 isn't the best performer at low queue depths) I had to try this drive out. I wasn't concerned about the boot times because I'm running an X79 system which only in rare circumstances can boot with NVMe.
But I already had a fast SATA3 SSD that booted and ran Windows very quickly. So (as I've mentioned before) I use my 400GB 750 to run programs and games, and it also acts as a cache drive for photo programs and holds my pagefile. This configuration runs very well, and although I know it's not accurate, it feels like the whole system is sitting in RAM, ready like never before.
Beside that I didn't want to 'waste' the 32GB it would take of my 400GB to have Windows installed on it.
So there's still a way to enjoy this drive's speed and avoid any boot slowdowns.