Nvidia’s RTX 50-series drivers feel half-baked, focus too much on MFG

Liberfi

Releasing a new GPU architecture is a complex affair. Nvidia should know this as well as any company, considering it’s been making graphics cards for 27 years now, every one of which needed drivers. But the Nvidia Blackwell RTX 50-series GPUs haven’t had the smoothest of launches. The RTX 5090 at least offers new levels of performance, while the RTX 5080 delivers only slightly better performance than the prior generation RTX 4080 Super. But both GPUs seem to be suffering from a case of early drivers and the need for additional tuning.

It’s not just about drivers, though — or perhaps it is, but for Blackwell, Nvidia recommends new benchmarking methodologies. It presented a case at its Editors’ Day earlier this month for focusing more on image quality and analysis, which is always a time-consuming effort. But it also recommended switching from PresentMon’s MsBetweenPresents to a new metric: MsBetweenDisplayChange (which I’ll abbreviate to MSBP and MSBDC, respectively).

The idea is that MSBDC comes at the end of the rendering pipeline, right as the new frame actually gets sent to the display, rather than when the frame finishes rendering and is merely ready to be sent to the display. It’s a bit nuanced, and in theory, you wouldn’t expect there to be too much of a difference between MSBDC and MSBP. Intel has also stated that MSBDC is the better metric and recommended using it for the Arc B580 and Arc B570 launches.

Part of the issue with MSBP is that it doesn’t necessarily capture information correctly when looking at frame generation technologies. And, in fact, if you try to use MSBP with Nvidia’s new MFG (Multi Frame Generation), you get garbage results. This wasn’t the case with DLSS 3 framegen, but MFG reports data in a different manner:

RTX 5080 with MFG 4X, MsBetweenPresents vs MsBetweenDisplayChange

(Image credit: Tom’s Hardware)

All of the fields shown are useful data, but with MFG 4X the values in the MSBP column now function differently. You can view it as the total time required for the GPU to render the frame in the traditional manner, so in this case, it’s about 27.66 ms per frame, followed by nearly instant “rendering” times for the three generated frames. The new flip metering hardware in Blackwell GPUs then attempts to evenly pace the actual display of the generated frames on your monitor.

Looking at the MSBDC column, we find a far more consistent sequence of frametimes, as expected. Instead of the “fast-fast-fast-slow” frametimes in the MSBP column, we get relatively similar frametimes of around 7.35 ms per frame. The MsBetweenSimulationStart column ends up giving the timing of user input sampling. So, in this case, the user input sampling happens every 29.18 ms, or at 34.3 FPS, while the generated rate of unique frames sent to the monitor runs at 136.1 FPS — basically four times the input sampling rate, as expected.

The above results, incidentally, are taken from Cyberpunk 2077 benchmarks running at 4K with the RT-Overdrive preset (aka path tracing or full RT), DLSS Quality Transformers upscaling, and MFG4X frame generation. As I noted in the 5080 review, the smoothness of the framerate as seen on the monitor does make the game feel better than if it were running at 34 FPS, but it also doesn’t feel like it’s running at 136 FPS because input sampling is happening at the base framerate of 34.

But back to the discussion of MSBP and MSBDC, it’s a relatively easy “fix” to switch between the two metrics. Also, without using framegen of any form, we’d expect the resulting performance metrics to look pretty similar. But “similar” isn’t the same as “identical,” and since I already had all of this data, I decided to take a closer look at what’s going on and how the new metric affected my benchmark results. It’s probably not going to be what you’d expect…

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