Can an old PSU result in frame stutter and input lag? +monitor suggesstion

[Argus]

If you haven't seen my other posts, basically long story short, a new psu is the only thing I have not yet tried in order to fix my stutter eyestrain issues.

I currently have a 7-8 year old EVGA 1000 watt PSU. EVGA SuperNOVA 1000 P2 220-P2-1000-XR 80+ PLATINUM.
The question is, how exactly do you determine what a "good" psu is and what features should I be looking for to have a "cleaner ripple" or whatever it's called?

What's a good brand and model to buy these days?

Also, I am looking for suggestions for a 165hz 1440p G-sync monitor. It seems like all new monitors are IPS but I would prefer TN or even VA if such a thing exists and fits the specs.

I've been looking at this AcerXB273U GSbmiiprzx https://www.bestbuy.com/site/acer-preda ... Id=6425562
But I've heard it has some issues where an extremely high overdrive setting is forced on when G-sync is turned on. What exactly does that mean for frame smoothness/pacing and stutter? Does anyone else have this monitor or know of a better one?
Thanks.

My current specs are:
10850K (Overclocked to 4.8 all core, 4.5 cache, 1.35 volts)
Z490 Maximus XII Formula
GTX 3080ti
Dell sd2716dg G-sync Monitor
Nvidia Driver 531.79
Logitech G502 set at 1000hz polling rate
4000Mhz CL16 2x16gb G.Skill ram

[bumbeen]

that's a killer PSU dude, I wouldn't trade it for anything tbh. the mobo has its own capacitors and voltage regulators so it isn't like the power from the psu rails is blasted straight in to the components