Windows 7 or 10 for i5 7500 for gaming?

Thanks.
Ye, I've decided to give Windows 10 a try.
I'm getting modded version with removed telemetry services and other burdening stuff, hope it will perform well in games.

Hello again.

Thanks for advice, but I won't use it (got activated Win10 for free from other "source" already, so nothing lost)

How the game performance looks now?

Even on modded Win10 version (polish pro x64 mod, with removed a lot of useless and user tracking stuff - even iso size is just 1.9 GB (!)) without correct setup I've had much worse performance than vanilla Win 7 x64 Ultimate SP1.

Tested few applications - Witcher 3, Tekken 7, CEMU with Zelda Breath of the Wild, Lords of the Fallen.
Same settings for those applications like on Win7. Same save game files for W3 and LotF, same mods installed for W3. Same drivers versions (just windows variant differs, but still same build revisions). Same nvidia control panel settings.

Without any changes in system, I got no change in CEMU performance, but massive stutters even in main menu of rest of the applications tested. Random anoying stutters in games which were not present on Win7. Crowded city in Witcher 3 (the big one in Novigrad? With harbour and shitload of NPC) unplayable due to massive fps drops and stutters, even with hairworks off.

I felt something was not right there... Total disaster...

Then I read about Win10 Creators Update and global drastic performance drop for a lot of people. Made some changes posted on internet:
- disabled game panel,
- disabled DVR both in Windows settings and in registry (disabling it in registry is very important!)
- kept "Game Mode" on,
# simple just disabled all options from Windows 10 gaming settings "Game mode" one (noticed some performance boost while testing "game mode" when it was in stutter and dropping fps state like crazy),

Set pagefile (2x of size of my current RAM, so 32GB) on SSD disk, had that feature disabled by default, without setting pagefile CEMU sends errors about too low RAM memory amount.

Disabled totally some more services, like Windows Update and Defender.

Disabled some more useless Micro$oft stuff - some things about sending reports, diagnostics, privacy, features that I won't even use etc. just explored near every setting section and disabled a lot of stuff. Spent some time there.

Disabled SSD disk indexing for every folder and file there. Disabled prefetch and superfetch there too.

I guess that's all I've done. After that results:

- Witcher 3 - Hairworks on crashed on Win7, now game runs with it on normally on Win10.
1080p resolution, Uber quality, Postprocesses maxed, hairworks on but lowest quality.
Stable 60 fps even in Novingrad? big crowded city with harbour, just in few single random locations (like some exact spot in Skellige forest near palisade etc.) I got stutters and drops max to 50 fps, nothing game breaking.

- Tekken 7 - everything same except I get rid of random stutters in one stage (Twilight Conflict). On Win10 it's crystal clear.

- Lords of the Fallen - no changes,

- CEMU Zelda BotW - Win 7 - minimum 27 fps, on Win10 it don't drop under 28 fps, shader cache loading faster, sadly my gamepad support gone in this emu...

So..... When I just fresh installed Win10 and hardware drivers and went gaming, I've got drastically worse gaming performance than on Win7, with ridiculous situations like stuttering in any game main menus.

But, after reading a thing on two on internet, messed up around with system settings a bit, I've got same peformance like on Win7 or even "nano-better" (dunno how to name it ) performance. Looks like peformance drops are just because infamous Creators Update.

I will stick with Win10 modded version, really like its interface too.

And tested some one more thing again on Win10 (tested it on Win7 too) - HPET (High Precision Event Timer).
I've heard some stories about it and effect on gaming performance. Sadly, there are different opinions about it - someone got boost when disabled, someone when enabled, etc.
While on Win7 changing it get no differences for me, on Win10 it makes difference in one game for me - Witcher 3.
While HPET off in both BIOS and system settings (through cmd) game runs OK (disabled default)
While HPET on in both BIOS and system settings I have random annoying stutters in crowded locations like cities, villages, enemies groups etc.
It has no impact on my tests before, was disabled before them.
But it can be worth testing for someone.