A:AnswerMan, your mother board is more qualified to run it than the board that I had it on, which was a MSI 7888 Jasmine with only a PCi-e 2.0, and it worked better than fine for me. I even played some games in full 4K at 60 fps. So I can only imagine that your board, which has a PCi-e 3.0 slot would actually run it even better than what I was running it on. Not to mention that my APU was an A8 6500b - a 13 year old chip. I say the board that I "had" it on because I just did a full computer upgrade by ditching my (just as of a few days ago) old PC in favor of getting something quite a bit more updated. But the short answer is, YES, it should be just fine on your H81M-H.
A:AnswerThis card is definitely capable of running Fortnite at 1080p with settings pretty much maxed out. 240fps I'm not so sure about. I run at 144fps.
A:AnswerI think what you are asking is if your i7 37xx CPU will work with this card. If that is indeed what you are asking. then the answer is yes, provided your motherboard's BIOS has UEFI and it is enabled. Not sure if your motherboard has UEFI enabled? In Windows 10, search for System Information, then verify the following setting - BIOS Mode: UEFI. I use this card on my i7 3770 desktop and it plays games at 1080p just fine. Obviously, my CPU is the the bottleneck, but it plays the games fine for me. Verify that your PC case has enough room. Mine barely fit in the case as the cards are much longer and taller than in the past.
A:AnswerYES, Should work great! I have the same card RX 5500 XT and got it installed with no issues. Per Oculus website, minimum required card for the Rift S is AMD Radeon RX 470, and this is better.
Good luck!