Hi,

 

Last time i upgraded was from I7-950 first generation to Haswell and all though frequency was only 5% faster the gain in FSX was about 30-35%. (4,2 GHZ vs 4,6GHZ)

 

Seeing Rob having a blast in P3D at for instance EKCH at about 30-40% increase in FPS vs my system i was wondering if this is mostly comming from an newer CPU generation ?

 

Thanks

Michael Moe

One of the main difference between FSX and P3D is that P3D moved many computations from CPU to GPU workload.

 

I may be wrong but I'm quite sure that Rob's twin Titan SLI'sed boards have a major effect on its P3D performance :smile:

Thanks  but if you put those CPU hocks sliders (traffic ? shadows? )calculations slider up and back the GPU sliders a bit it might be easier to determe.

 

I have 2 GTX970 Superclocked in SLI (which does not work well as allready mentioned elsewhere) and dont think all that extra power only comes from those TITANS. At least i hope not. 

 

There was once a "general" rule that making a new step up on the CPU generation would give you about 10% increase in FPS. 

 

But thats from the older FSX days i know.

 

Michael Moe

One of the main difference between FSX and P3D is that P3D moved many computations from CPU to GPU workload.

 

I keep on hearing and reading that, but I have never seen a comparison made by a tool which precisely measure and compare GPU LIVE utilization between FSX and P3D 2.5.

 

Just to gauge this fact and to wipe the ghost who tells that it is only a marketing mantra.

I keep on hearing and reading that, but I have never seen a comparison made by a tool which precisely measure and compare GPU LIVE utilization between FSX and P3D 2.5.

 

Just to gauge this fact and to wipe the ghost who tells that it is only a marketing mantra.

There you go Mark - something to occupy your weekend!  Let us know your findings! 

 

I'll be busy flying. 

 

@MichaelMoe - I have two 970's and, as you might know, have had NO issues with SLI for over a year. Even though P3D is optimized for more GPU processing, it is still possible to overload the GPU and then you will get a drop in FPS as the CPU has to carry the load.

 

IMHO P3D is more critical to balanced sliders than FSX ever was.

 

Vic

I think we'll see the performance distance grow even more from P3D over FSX when/if P3D moves to DX12.  Many of the hurdles going from DX9 to DX11 have been addressed (with the exception of a few FX perhaps not working as well as they could which are being addressed in v3).

 

DX12 will certainly free up the CPU -- with early demos of other games showing about 50% less CPU resources -- that's significant.  I'd dare suggest it'll bring over mid to lower end GPUs and CPUs that could show VERY good performance in P3D with high graphics settings.  Don't get wrong, there will always be a need for as much CPU/GPU as you can toss at a flight simulator, but DX12 might turn those "wish I could afford that visuals" into a reality.  The majority of end users don't have multiple high end GPUs, nor top tier CPUs, etc. etc. ... according to Steam they estimated the median PC to be around $1000, Maximum PC has the mid-range PC at around $1300.

 

 

 

tool which precisely measure and compare GPU LIVE utilization between FSX and P3D 2.5.

 

It would be impossible to be exact given the LOD Radius differences and features that P3D supports (tessellation, volumetric fog, cloud shadows, etc. etc.) that FSX doesn't.  The best you can do is turn those features OFF and then compare, but in doing so you are removing GPU bound processing (that DX11 can handle) so you will skew results because you're forcing CPU bound compares.

 

It's really hard to do a side by side compare when one product doesn't support the same graphical feature set as the other.  If you're looking for feature to feature compare, you'd be better comparing P3D performance to XP10 performance as you could at least enable feature sets that are intended to be similar.  I've done P3D to XP10 performance compares using same feature sets, also done compares with FSX but with the understanding I'm just shifting resources to be CPU bound.  I've done FSX to FSX-SE compares ... "out of the box" FSX-SE does perform better than FSX, but add commonly known "tweaks" to FSX and it performs very similar to FSX-SE.

 

But agree with Vic, it's about balance ... and finding that balance and figuring out what you can live without.

 

Cheers, Rob.

[quote name="vgbaron" post="3262989" timestamp="1435949698"

 

@MichaelMoe - I have two 970's and, as you might know, have had NO issues with SLI for over a year. Even though P3D is optimized for more GPU processing, it is still possible to overload the GPU and then you will get a drop in FPS as the CPU has to carry the load.

 

IMHO P3D is more critical to balanced sliders than FSX ever was.

 

Vic

 

 

 

 

Hi Vic

 

I would Really like to see your pc settings as i have no clew what is going on. We are a few with the same symptoms. (right mouse click issue or hitting the menubar)

 

Thanks Michael Moe

Hi Rob

 

That is good news. No need to upgrade my CPU then. Project Cars is also looking in to a 25% fps boost with DX12 just because DX11 code is better optimized so i heard.

 

Thanks Michael Moe

http://forum.avsim.net/topic/470158-does-sli-users-have-seen-less-visual-artefacts-with-35306-nvidia-drivers/page-2#entry3254830

 

 

Here you go Michael  - the relevant post is #19.

 

Vic

I think we'll see the performance distance grow even more from P3D over FSX when/if P3D moves to DX12.  Many of the hurdles going from DX9 to DX11 have been addressed (with the exception of a few FX perhaps not working as well as they could which are being addressed in v3).

 

 

 

 

 

But agree with Vic, it's about balance ... and finding that balance and figuring out what you can live without.

 

Cheers, Rob.

 

What will be interesting Rob, and I would welcome your opinion on this greatly, is that DX12 will likely delay my PC upgrade.

 

I am still on the i52500k on air (overclocked ot 4.7ghz) and that chip has been so good to me. I am delaying upgrades until the intel chips late this year early next year.

 

Now, with my gtx970 I wonder if I would be able to get another year out of the 2500k. Also, I wonder if there will be a need for heavy overclocking IF p3d goes DX12

 

Alex

 

 

is that DX12 will likely delay my PC upgrade.

 

Sounds like a sound plan

 

Many are doing exactly that.

 

Cheers, Rob.

Sounds like a sound plan

 

Many are doing exactly that.

 

Cheers, Rob.

Thanks for the info Rob. Currently have 4770k and single GTX780. With the CPU improvement relating to DX12, would it make sense to keep the current CPU and upgrade GPU to SLI?

 

Thanks

One of the main difference between FSX and P3D is that P3D moved many computations from CPU to GPU workload.

 

FSX does shadows, HDR lighting, and water on the GPU.

 

Even though P3D is optimized for more GPU processing, it is still possible to overload the GPU and then you will get a drop in FPS as the CPU has to carry the load.

 

The CPU doesn't carry the load, it passes the load to the GPU through the PCIe bus. If the bus is slow, it would cause the FPS to drop, not the CPU.

FSX does shadows, HDR lighting, and water on the GPU.

 

 

The CPU doesn't carry the load, it passes the load to the GPU through the PCIe bus. If the bus is slow, it would cause the FPS to drop, not the CPU.

Yep, and I think we have yet one game or device that can really saturate a PCIe x16 bus. So there is quite a bit of headroom in that area.

Guys,

 

games in order to take advantage from DX12 MUST be written from scratch with this concept in mind.

 

FSX and P3D have been written when DX12 were only a concept in the air, nothing more.

 

So, unless you develop a flight simulator from scratch both FSX and P3D won't take advantage from DX12, unless few very minor aspects that have almost no impact on FPS, many users have already witnessed that, also in this forum / thread.

 

Don't believe the hype of Microsoft that is trying to instill into potential customers' brains, that's only marketing stuff based on players' hopes and fake MS press articles published just for marketing subliminal reasons.

DX12 MUST be written from scratch with this concept in mind

 

Hi Mark,

 

DX12 was added to Win 10 build 10041 onwards ... you can test out any DX12 API work you might be doing with that build.  

 

You definitely do NOT need to re-write your application from scratch to use DX12 ... in fact many of the engines using UE4 or Unit5 are already working.  The transition from DX11 to DX12 isn't a massive undertaking, here is Direct3D 12 Programming guide: https://msdn.microsoft.com/en-us/library/windows/desktop/dn899121(v=vs.85).aspx

 

Here are the specifics about porting DX11 code to DX12 ... 

 

https://msdn.microsoft.com/en-us/library/windows/desktop/dn913194(v=vs.85).aspx

 

Microsoft are clearly making the transition from DX11 to DX12 easier, but there is nothing I'm aware of that helps transition from DX9 to DX12 ... for those DX9 (like FSX) apps it will require more work.  For DX11 apps like P3D it will require less work.

 

Cheers, Rob.