Questions about GPUs and PCI_E Gen 5.

[Thinder]

I checked on my own GPU specs, that of NVIDIA 4080 and 4090, I can't see any of them supporting PCI_E Gen 5, yet, the DDR 5 systems relies on the 64 GB/s X 16 to get the performance increase manufacturers claim for their new tech motherboard, CPU and RAM.

So what gives? Is there any GPU supporting the 64 GB/s X 16 of PCI_E Gen 5 today or does it depend on the GPU bandwidth limits only?

In any case in the event that there is no GPU support for PCI_E Gen 5, once the player start using Multi-Threading in DCS she/he will quickly hit a GPU bottleneck, that's what my Sapphire Radeon RX 7900 XTX clocking as high as 3000MHz end up doing from a <> 15% CPU bottleneck.

Multi-threading is already a huge improvement in terms of performances in DCS, but the drawback is that the GPUs are now the weak links of the systems we put together, with faster CPUs than my 7 5800X 3D, the difference will be even greater.

There's no way I'm gonna push mine further, I'm not planning to watercool my GPU, only the CPU which Max Operating Temperature (Tjmax) is only 90°C, yet higher than the 7800X3D, 7900X3D, 7950X3D (89°C), so AMD players better watch this cooling...

So I have to live with this new situation, even before the final release of DCS MT engine and see where gains can be made; frame times come to mind, but also better case and CPU cooling.

Your opinions...

Edited June 15, 2023 by Thinder

[Thinder]

What GPU has PCIe 5.0?

[SkateZilla]

no GPU Currently on the Market even uses 100% of the PCie 4.0 x16 Slot Bandwidth.

Why Add development expense to the card, just to add the PCIe5 Interface controller to it, when it offers nothing.

The ONLY PCIe5 Devices I've seen are M.2s, and even the performance between them only benefits Sequential Writing, the Random Read/Write is pretty much the same between the two.

 

Honestly, MT Added the Ability to Separate Rendering Thread from the sim thread, 
So Heavy Sim Thread Load doesnt Kill Rendering thread performance, leading to Low FPS / GPU Usage.

The bottleneck now isnt the "GPU", it's the Rendering API (DirectX 11).

Edited June 15, 2023 by SkateZilla

[Thinder]

7 hours ago, SkateZilla said:

no GPU Currently on the Market even uses 100% of the PCie 4.0 x16 Slot Bandwidth.

The bottleneck now isnt the "GPU", it's the Rendering API (DirectX 11).

 

Thanks for your reply, it's good info for everyone.

It still isn't PCI_E Gen 5, and yes, there still are ways to gain FPS with PCI_E Gen 4, something I need to explore, I know there is a bottleneck in the Rendering API, I just haven't got the full picture yet to try to tweak it, if you have a fix, you're more than welcome to post it...

In my screenshot, there is no reason why the GPU only produce 66FPS, especially because the frame time is relatively low, I think there still is more to come from this combo.

Note that my goal here was to demonstrate the lack of maturity of the DDR5 systems, I had a clue looking at the available RAM specs, no equivalent of B.Die there yet, and the RYZENs are designed for lower latency, even the 7000 series, so investing in a DDR 5 system to play DCS today is perhaps not the best option.

Edited June 16, 2023 by Thinder

[actually_fred]

It's really just a curiosity and doesn't make sense, but the Moore Threads MTT S80 has PCIE gen 5 - while delivering worse results than a GTX 1050ti, at around 5x the watts per frame.

[SkateZilla]

9 hours ago, Thinder said:

Thanks for your reply, it's good info for everyone.

It still isn't PCI_E Gen 5, and yes, there still are ways to gain FPS with PCI_E Gen 4, something I need to explore, I know there is a bottleneck in the Rendering API, I just haven't got the full picture yet to try to tweak it, if you have a fix, you're more than welcome to post it...

In my screenshot, there is no reason why the GPU only produce 66FPS, especially because the frame time is relatively low, I think there still is more to come from this combo.

Note that my goal here was to demonstrate the lack of maturity of the DDR5 systems, I had a clue looking at the available RAM specs, no equivalent of B.Die there yet, and the RYZENs are designed for lower latency, even the 7000 series, so investing in a DDR 5 system to play DCS today is perhaps not the best option.

 

The API Bottleneck can't be fixed,

Which is why ED is Moving DCS from DX11 to Vulkan,

Somewhere in the Vulkan Thread, I broke it all down in the Vulkan thread a few times..

but:

 

[Thinder]

2 hours ago, SkateZilla said:

The API Bottleneck can't be fixed,

Which is why ED is Moving DCS from DX11 to Vulkan,

Somewhere in the Vulkan Thread, I broke it all down in the Vulkan thread a few times..

but:

 

Thanks for the infos.

As I expected we are gonna have to wait for Vulkan to finish fine tuning MT in this game, I hope it will help the GPU to keep up with the CPU,  I never thought possible to see a Ryzen 7 5800X 3D bottlenecking a GPU running at 3000MHz.

What can we expect from Vulkan in term of performances compared to the actual MT?

I remember 3DFX, I had a Voodoo GPU once...

 

Edited June 16, 2023 by Thinder

[SkateZilla]

I cannot comment on expectations sorry.