I need a programmer, this could help for sli microstutter

[Danybonin]

Hello, not everyone might understand but anyone familiar with using a fps limitter in game will understand.

first sorry for my poor english, it's my 2nd language. Please read all my post, i hope you will understand what im asking. Im a sli user and gsync @ 144hz user. I have a sli of titan x and the rog swift monitor. I have high fps in games but with sli, in many games i still see some stutter/micro-stutter, even in the 90+ fps range. Single card is generally butter smooth. I discover how much using RTSS as a fps limitter was awesome. For exemple, in GTA5, with my setting, in town, im in the 90 fps range, but still see some stutter. Putting fps limitter to 80 fps help a lot. In fact, with sli, i discover that if you set a fps limitter and the fps never go below that fps, sli feel smooth. So i run locked at 80 fps, and its smooth. But when i go outside of the city, fps go below 80, and even at 70 fps, i start to see some stutter/micro-stutter again. So if i take down the fps limitter to 65fps, every thing is smooth again. But if then i go at the worse case in the game, fps can go as low as 55 fps. Then again, if i put a fps limitter to 50, smooth again. So to have a 100% smooth experience, i would have to limit at 50fps. But that is a bit low, when i can get 90+ fps elsewhere in the game.

So what im asking to programmer, is there a way make a dynamic fps limitter?
Like it would go down as fps go down, and it would go up only when enought power to not fall back so quick. I don't know if you understand what i mean? A bit like nvidia did with their "smooth vsync" option, in the manner that when it drop to 30hz, it wont go back up to 60hz until it have high enought fps to not fall back to 30hz too soon. That would be fantastic if someone could do that. That is the only way to enjoy a real smooth experience with gsync + sli +144hz. Im very sencitive to any form of stutter, and i can't live without RTSS now, but would be so great if a dynamic fps limitter would be possible.

I was thinking why not limit fps in fonction of the gpu 1 usage. I know sometimes you can be below 99% usage for different reason (ex. cpu bound situation), but i was thinking about something. If you try to maintain, let say 92% gpu 1 usage by the fps limitter, you should then be a few fps below what you can acheive. So if i play GTA5 and im at 90fps at 99% usage, then if the dynamic limitter try to keep gpu usage at 92%, he will limit to maybe 80 fps. If i move out of town and fps start to drop, the gpu usage will start to climb up, then the fps limitter, trying to keep gpu usage at 92% will then lower the fps. So if i dropped to 70 fps, the limitter will now limit to lets say 65 fps. Maybe this could be a way of making a dynamic fps limitter? There could be a minimum limit to maybe 30fps, even if gpu usage is 99%, and a maximun limit, maybe 144fps, if gpu usage is very low (ex. in a video cutscene) I really think this is something needed with gsync + sli + 144hz. Of course fps will be a little lower, but with gsync, high fps doesn't matter if frame pacing is not good. I hope someone could program this. Probably not an easy task, but if anyone think he can do it, let me know please.
Thanks you very much

[RLBURNSIDE]

I worked on SLI ports for multi-GPU (up to 4 cards) and I don't recommend multi-GPU until DX12 SFR comes out. AFR adds an extra frame of latency and generally is a poor price-performance tradeoff.

Windows 10 is coming out soon, if I were to contribute to something like this, it would be an SLI AFR -> SFR converter dll wrapper. So, render DX11 titles in DX12. But that's probably a ton of work.

Yesterday there was a g-sync driver update for windowed G-sync compatibility. I would wait on NVidia to solve this if they can. They added ULMB control to the driver now so I wonder if that's a precursor to making it work with G-sync at the same time. I can't wait to see what's in store.

What games are you playing right now? I just picked up Project Cars and Drive This Track. About to try Drive this Track on my Acer 1440p with g-sync, but Project Cars was sick smooth, like butter.

DX12 is going to revolutionize and massively improve SLI, trust me. SFR across different GPU vendors or even intrageneration is going to be very powerful. If Card A is 2X the power of Card B, then Card A does 2/3rds of each frame's rendering. But still keeping input lag to 1 frame.

[Danybonin]

Yes im also looking foward to dx12. SFR will offer less scaling of course, but should be better for gsync @ 144hz user. SFR was used in the past, but was not working good i think?

I know about that latest nvidi driver but seams to be a buggy one... User selecting gsync windowed mode, were seeing much lower fps even when gaming in fullscreen. I don't understand why people want to have windowed gsync, i never play in windowed mode. I think it's mostly RPG players that need to switch to desktop or other program often... if not... why run in windowed mode?

Project car run smooth aslo, but if you put all max setting and AA to ds9x and ultra smaa and under heavy rain, not so smooth. But it is not a game that i would need a dynamic fps limiter so much. Dying light is running good also with sli+gsync. Some games micro stutter more.

GTA5 run smoother with fps limiter. But sadly if fps fall below the limit i putted, then the stutter come back.

Witcher 3 is a total stutter fest with gsync @ 144hz if not using any limiter.

Metro last light, run pretty well with sli + gsync @ 144hz at 1440p, but put enought SSAA to be in the 45-55 fps range and it is a stutter fest. The same fps range with single card feel so much smoother than with sli. Puttting fps limitter to 40, in the situation i described (45-55 fps with sli) and it is very much smoother.

gsync is suppose to be smooth even in the 45 fps range, and with single gpu it is. But with sli, it is generally not. I tryed it with total different system also. Same result. Sli + gsync not smooth sometimes.