Sorry for updating this thread rather late, but I've been a happy user of the numerous tweaks suggested by Keith on my music PC (Win 2012 R2 Server) for two and half years now.
Few days back Keith had come up with a new software to not just set priorities of computer processes but to also their quantum. He's given option to choose 12 different settings (not that I know what they mean, or the implication of choosing an option).
Here's a screenshot of the tiny software (just 22 kB):
I tried all the options one by one. The difference between options is subtle, but the difference between not using the "Set Priority Quantum" and using it is not at all subtle. With this software running in the background (run it as admin), there is a sudden drop in the noise floor of my computer playback. I was so intent on trying to discern the differences between the various options that I initially failed to recognize the new elephant in room (in a manner of speaking). It was only after I changed to another track that I realised the jaw-dropping increase in resolution of tiny nuances in the music. I also noticed that the decay trail had bloomed, making music sound very natural and relaxed. I wanted to turn up the volume as it wasn't fatiguing my ears despite the louder than usual SPL.
After going through all 12 options, I shortlisted 3 as possible finalists. One is most balanced, overall (to my ears). The second has a frantic attack and brings out fine texture in the music, though the edge can harden sometimes on certain tracks. The third is geared more towards a sweet decay. All valid choices, IMO.
This tiny software has had the effect of a major hardware upgrade to my sound. Proof: I listened to music till 2 AM last night
If you use Windows for playing music in any capacity (standalone machine running your favourite music player, or for something like a Roon Core), I strongly urge you to try this optimisation software.