Dead Space Performance Jumps 46% with Resizable BAR Enabled

[TheinsanegamerN]

The fact that ReBAR isn't yet enabled for all games on NVidia GPUs, or at least enabled by default (denylist instead of allowlist), is a sad joke. NVidia fans are quick to jump on Radeon driver issues but it's time to own up to this.

ReBAR is a strict improvement in the PCIe protocol with absolutely zero tradeoffs. Any scenario that regresses performance with ReBAR-on can only be caused by a deficiency somewhere (game engine, GPU driver, or GPU architecture - more likely the latter two, especially for recent releases). Intel's Arc GPUs have an even bigger dependency on ReBAR because it's a new arch so they didn't bother to optimize the ReBAR-off case, and that's the right thing to do since every minimally current CPU/chipset/motherboard also supports ReBAR. I suspect RTX GPUs are the opposite, they probably still have drivers and maybe even memory controllers over-tuned for the ReBAR-off case, causing more regressions than any competing GPU if you turn it on for all games.

It has no tradeoffs except for all the times it results in worse performance.

Do you even think about what you type? AMD and intel blacklist software that suffers from ReBar, so clearly it has some tradeoffs and compatibility issues.

 

[mechtech]

I thought resize bar was on by default? So all benches should already have that included in their benching.

I know W1zz told me one time that all modern systems have resize bar on by default, so this should be a null find.

Off by default in my bios.

 

[Makaveli]

It has no tradeoffs except for all the times it results in worse performance.

Do you even think about what you type? AMD and intel blacklist software that suffers from ReBar, so clearly it has some tradeoffs and compatibility issues.

To be honest i've had Rebar on since day one and zero issues if there as been any performance regression on certain games it certainly haven't been noticeable during major game play. Probably 3-5 fps here and there. And I prefer AMD approach to just whitelist everything instead of an approved list.

 

[ThrashZone]

Hi,
Fairly useless on older gpu and board older than z490 so congrats

 

[HisDivineOrder]

Just tried it and see substantial improvement, but nowhere near 40%. Mine went from 75 fps @4k with 100% usage and 330-360 watt power usage to 90-95 fps with 100% usage to 390-410 watt power usage. Using 4090 @4k resolution.

Thing is, I suspect the 4080 and below when doing higher resolutions are using Resizable BAR to get around their relatively narrow memory buses. The 4090 is a beast and probably doesn't feel the pinch in the same way.

 

[matar]

I have it enabled since day 1, but it's good to know that it does make a difference.

 

[R00kie]

With what limited testing I could do, I can safely say this hack definitely works, the framerate improvement is around 10-15 FPS on an undervolted and power restrained RTX 3080 on my ultrawide, and it might have also improved the frametime variance, but I have to play a bit longer to know for sure.

 

[joemama]

With what limited testing I could do, I can safely say this hack definitely works, the framerate improvement is around 10-15 FPS on an undervolted and power restrained RTX 3080 on my ultrawide, and it might have also improved the frametime variance, but I have to play a bit longer to know for sure.

What are the actual FPS numbers before and after? A 30 increasing to 45 is way different from a 160 increasting to 175.

 

[R00kie]

What are the actual FPS numbers before and after? A 30 increasing to 45 is way different from a 160 increasting to 175.

So the flight-through through the fridge section in Hydroponics with ReBar enabled had us at around 95-135FPS, with it disabled the framerate was hovering around 80-115, that's with all settings maxed out and with DLSS/FSR Disabled at 2560x1080, but unfortunately ReBar did not manage to fix the stuttering, so I guess that could only be game related.

 

[Warrior24_7]

I don’t trust bench marks from certain YouTube wha+k jobs. There’s and article out right now saying that RTX 4090 can’t run this game at 60fps in 4k with everything on! I bet this is the reason why.

 

[Bigshrimp]

I enabled ReBAR through the Nvidia Profile Inspector and it did in fact help make the game a whole lot smoother with a 3080 Ti, NVME SSD, AMD 3900X, and 32gb of RAM. I also changed the power setting to AMD Ryzen High Performance and disabled the Control Flow Guard through the Exploit Protection settings for Dead Space Remake. After doing all of that, I am 99% stutter free. I only get a small stutter when I first load my save and enter the game.