dGPU on HDMI?

Hi.

I'm about to pull the trigger on a new laptop for development purposes. It is however extremely important that I get a laptop that has the HDMI port is wired to the dGPU. This is for Oculus dev work reasons and is to insure compatibility with Direct Driver Mode.

I'd like to get the P650RE3 in particular and while quite a few people can confirm that Display Port 2 is directly connected to the dGPU there isn't much regarding the HDMI port.

Now on the Clevo site the following specification statement is made:

• Support NVIDIA® Surround View via HDMI x1 and miniDP x2

Now does nVidia's Surround View mean that in fact that the HDMI is also wired directly to the dGPU?
And if not can anyone suggest an alternative laptop?

thanks in advance.

J

 

The P650/P651 have the HDMI and DP ports connected directly the Nvidia dGPU. When you switch between dGPU and MSHybrid in the BIOS it only affects the internal display and when set on dGPU it allows G-Sync to function if you buy that version of the laptop.

 

I believe the P870dmg models will work as well or any laptop that doesn't use optimus or internal gfx switching. The Oculus forum boys will harp all day "Laptops arent supported" which doesn't mean that it won't work (Many individuals have used laptops with their DK models). You just need the right equipment and they don't offer any help which I think is a reflection of poor support in all honesty. I have the CV1 on preorder and will be using it on a laptop and desktop both.

When the P870dm was released they were testing a VR device and it looks just like what is now the CV1 of oculus so I think it was a test model with a different label on it.

 

Be interesting to see oculus support on laptops as the inevitable launch approaches. guessing we will be seeing a lot of threads here

I'd think the 970m would be a little weak for it but only time will tell really.

 

You certainly will have support from the HTC vive as they are going for a more mobile setup and seem to like the idea of having a notebook on the back with a large extra battery.

 

@XMG Thanks for the info on that model.. much appreciated.. As for does Oculus work on Laptops? the answer for the DK2 (at least) is 'Yes'. I'm currently doing development with UE4 and the DK2 using a Asus G751JY (980m)..

I think the reason why Oculus isn't officially supporting laptops with the CV1 (two draw calls @3k @90hz) apart from the obvious 'raw power' issues is that there are so many different implementations of dGPUs on laptops. You have to have the dGPU exposed on the HDMI port for the Direct Drive mode to work. I'd imagine it'll be a nightmare for the Oculus Community Managers if they let this device spread too early on too many different specs of hardware.

So their decision to limit it to desktop hardware of a certain specification makes sense.. It reduces their launch risk considerably

 

I agree, at min a 980m and 980 desktop size is going to be optimal to run it smoothly. I don't see a low TDP limited cpu doing well either because of the 90fps wanted for smooth play.


Sent from my LG-H901 using Tapatalk

 

While it is true that there are subtle differences between different laptops models (i.e. some use NVIDIA Optimus, some do not), our models XMG U716 and XMG U726 with GTX 980 are officially deemed to be "VR-Ready" by NVIDIA. These 2 models already meet all requirements, including HDMI 2.0 with direct dGPU connection. If you run the Oculus compatibility app on those two models, you will get a positive results.

To prove our point, we are sending a XMG U726 to HTC Corporation right now - they will use our machine for some of their demo events in Europe, among others.

 

Thats some interesting news with HTC, I only made my consideration with Oculus simply because of how long they were in dev so I figure the support will be better and the fact that they seem to be focusing around a personal space rather than an entire room space. With the VIVE stating to have a camera to view the outside world without removing the headset that was a bit of kick to Oculus, I would have liked to have that option otherwise people will be clowning around you making fun and taking the headset off and on constantly will be a pain. The great thing is with two there is competition so it should drive both companies, 2016 is going to be interesting for VR without a doubt. If you can share any news you get from HTC, if you can't we know the drill and understand.

 

@GTVEVO - indeed, competition always drives technology and hopefully also pricing! We'll be publishing more information on our VR relationships (have been working closely with several developers and companies) including HTC on our website and through social media. I'm limited to what I can post on here as a reseller but any content from us sould be easy to find through Twitter and Facebook updates!

As I can't link to our website, I have pasted our FAQ article on VR below which might provide some further helpful information. It is based on what developers and the hardware companies have told us and reported, plus our own experience with the hardware and our laptops (the XMG/Schenker models listed are P6/7**R*, P7**DM and P870DM):

"To ascertain the compatibility of VR headsets such as Oculus Rift and HTC Vive with our notebooks and desktop PCs we must address two aspects: display connection and 3D performance.

Display Connection

Both headsets will come with a resolution of 2160x1200 pixels and a refresh rate of 90Hz. To drive this resolution and refresh rate, the laptop or PC requires at least DisplayPort 1.2 or HDMI 2.0.

The data sheet of the Oculus Rift states "Compatible HDMI 1.3 display output" as a minimum requirement, but this is a little confusing. Very few notebooks that were released with HDMI 1.3 or HDMI 1.4 have enough graphical power to meet the display bandwidth requirement for VR. To be on the safe side, HDMI 2.0 and DisplayPort 1.2 should be the minimum specification that you look for in a VR ready machine.

The graphical signal path is critical: the hybrid graphics solution NVIDIA Optimus (also known as "MSHYBRID") is explicitly not supported. The VR headsets must be directly connected to the dedicated NVIDIA or AMD graphics card; Optimus/MSHYBRID systems which route the Nvidia dGPU output through the Intel iGPU are not supported.

In terms of display connectivity, the following models are therefore, according to current information (Jan 2015) compatible:

XMG P506
XMG P706
XMG U505
XMG U705
XMG U506
XMG U706
XMG U716
XMG U726
SCHENKER W505
SCHENKER W705
SCHENKER W506
SCHENKER W706

The P506 and P706 can also support Optimus/MSHYBRID but this BIOS level switch only affects the internal display – all the external outputs are permanently connected to the Nvidia dGPU as with the other models listed above.

However, this applies only if corresponding powerful graphics cards are installed. This brings us to the second part of the FAQ:

3D Performance

NVIDIA and Oculus Rift have defined that at least the desktop graphics card NVIDIA GeForce GTX 970 is needed to get the full VR Experience. By comparison, the notebook graphics card GTX 980M is about 5-7% below the GTX 970 desktop graphics card.

Officially, "VR Ready" in the notebook sector are therefore only machines with the GTX 980 (without "M") in the XMG U716 and XMG U726.

But what is meant by "Official VR Ready Experience"?

Although the technology will run and work at lower FPS, from testing the recommendation is that a target of 90FPS should be aimed for in order to enjoy the full immersive VR experience. In addition, the headset should always be operated at its native resolution since the image quality deteriorates very noticeably at lower resolutions. This helps explain the minimum “official” requirements, because not only will you be running today’s triple-A titles (the Oculus Rift is being bundled with graphically demanding games such as "EVE: Valkyrie”), but also at 2160x1200 resolution. One can conclude that future VR titles will exploit these minimum requirements fully.



As with non VR hardware, there are many performance enhancing settings in-game which can be tweaked in order to reach a high FPS but also preserve image quality. For example texture settings, shader effects, lighting effects and so on can be adjusted and optimised in order to give the best VR experience

In addition, we expect a certain number of independent games which will be developed firstly for VR (over standard non-VR gaming displays) which will be considerably less graphics-heavy and thus run more efficiently on VR devices.

Nevertheless, considering the purchase price of €699 / £500 for the Oculus Rift it should be supported and driven by the best graphical hardware available. The XMG U716 or U726 XMG with the GTX 980 therefore provide the ultimate VR mobile experience.

At the moment there is no certainty over GTX 980M compatibility. This is due to the fact that the GTX 970 desktop GPU is the “official” minimum requirement and that the 980M is slightly less powerful. We do not expect to see hardware lockdowns and compatibility restrictions on sub-official performing graphics cards, however at this point in time the actual compatibility across the whole 9**M series has not been confirmed."

 

Well said, and as mentioned there is no hardware lock down so if your system can meet the requirements you should be able to run it at the performance that the machine can handle, just like the Dev 1 and 2 kits where used on mobile cards (not officially supported). I only mentioned the 970 because usually they score graphics in 3dMark around 102XX give or take. My 980m stock clocks scores 105XX just how it sits every day. Currently with new titles like JC3 I run + 100 or + 200 on my 21x9 monitor and the graphics scores over 12000 which is knocking on 980 desktop territory so if your hardware can handle it then its possible but there is still quite a bit of unknown since its just not out yet and we all have till the end of march

 

Awesome information from everyone here!

I might have to look at a 980m over a 970m for my purchase. I'd love to get a lappy with MXM support or even a GXX 980.. But simply can't afford it.

FYI I'm starting a Masters by Research project this year and am looking into leveraging VR technology into the realm of whale conservation.. Not sure if anyone here does corporate sponsorship for worthy projects?

 

For serious VR development I really think you would want the 980M, the desktop 970 is recommended as a MINIMUM and really you want more than that to be fair.

 

For general VR use, 980M will suffice but for VR dev all our partners use GTX 980 minimum as they need to work from the top down.

 

Working from the top down to be fair at the moment needs to be SLI 980ti really, the 980M will act as a good minimum entry.

 

Dual sli 980m or even 970m should have the power too! Any which way the theoretical fill is enough for the required render target x frame rate.. This however really depends on the complexity of the deferred renderer.. As for actual development alot occur in a cut down manner anyhow. Certainly optimising a game to run at 75 hz on a laptop GPU means a guaranteed performance on a desktop GPU.

The shear horse power required is to ensure a 'nausea' free experience for the user.. If you have used the a HMD you'll know how much this matters.

 

I wouldn't rely on SLI for VR.

By the way, it's false that 970 is the minimum, it's the recommended spec. There is a large difference between the two - Oculus has said that all apps on their store will be optimized to perform perfectly on a GTX 970. The 980M really isn't that far behind the 970 and has a huge frame buffer advantage which may play into its favor, time will tell.

 

Yup of course, this is what myself and @jamiet76 are getting at It's not that there's a hardline level of GPU performance at which you simply can't run the VR hardware, it comes down to (in smplistic terms) how many FPS you can run at 2160x1200 res with the hardware. The target is 90 - I've seen the difference between this and 75 and it's noticable - not in the same way that you can see the difference between 60Hz and 120Hz on a panel but because your body is immersed in the experience. Run it at too low an FPS and you start to introduce varying degrees of motion sickness, though of course someone who gets sea sick easier will also find lower FPS in VR less comfortable that someone who doesn't suffer as much.

As mentioned, 980M is only ~4% slower than GTX 970 and yes the tech runs fine on a 980M, but keeping at 2160x1200 requires quality settings to be reduced to be able to keep the frequency up.

 

For a full experience you will be wanting 90FPS minimum at 1440p, I am relying on the experience of those who have been working with the equipment on this.

 

will this work with the np9377sm-a SLI 980m's?

 

As we keep saying:

;-)

Oculus and Vive run at 2160 x 1200, that's below 1440p. I know what runs because of the extensive testing we have carried out in house ;-)

 

Then you have to factor in the large jump in GPU performance we are going to get over the next year or two and that starting development now you are going to be in the 2nd wave of titles for the platform.

 

nVidia is betting on it with its gameworks VR. With each GPU handling a different drawcall. Definitely makes sense.

I was pretty sure a GTX 970 is ~25% faster than a 980m.
http://gpu.userbenchmark.com/Compare/Nvidia-GTX-980M-vs-Nvidia-GTX-970/m15596vs2577

While this is true its not the full story. The actual framebuffer is of a much higher resolution in order to allow for the postprocess distortion of the frame peripheral. The card has to render to a higher resolution to achieve this so any discussion about resolution has to account for this process.

While nVidia has 'multi resolution' rendering.. It does not completely negate this need.. Rather reduces this pixel waste overhead. However it's too early to say what real world performance boost this will give.

FYI this article has a good breakdown and explanation of nVidia's approach to performance.

http://www.roadtovr.com/nvidia-takes-the-lid-off-gameworks-vr-technical-deep-dive-and-community-qa/

 

I'm more pointing to the fact that nvidia SLI support in general has been a total miss lately. VR is definitely going to be a gamble as well.

Oh and the GTX 970 was between 4 and 25% faster than the 980M on release but things have gotten much better with custom vbios and driver improvements without even taking overclocking into consideration. Its probably around a 10-15% total difference with a vbios that doesn't throttle although again the 980M wins when it comes to the framebuffer which can change things considerably.

 

VR has been a miss partly due to temporal rendering techniques requiring data from the previous frame and other such techniques, for VR you have two distinct view points so you can apply these techniques but keep them consistent to each point of reference. This means you can't scale out to 4 cards but 2 should not be an issue.

We won't see perfect scaling by any means but even a decent increase to frame rates and input latency will help a lot.

 

@jamiet76 Of course, agree completely. Often find myself simplifying answers on here because we spend a lot of our time trying to put in real world terms what our customers will actually need and experience.

 

Yeah I think we are technically knowledgeable enough to get each others drift.. Certainly typical consumers only want to know if it works or not.. I'm trying to ascertain what specs I can get away with actually doing VR development.

My product won't be for consumers but more conservation research.. So I have some latitude there. If I can get a 980m to perform close to a 970 I'll be completely stoked. Then I can acquire a lightweight powerful laptop for my research that'll also leverage the iGPU for 4hr lectures.. Win win in my case.

Thanks to everybody here for you're technical input and know-how.. I'm sure we have educated a bunch of casual observers here..

 

I'd be interested to see how a stock 980m would handle VR, then how it might handle when overclocked. It will be nice once Rift and Vive headsets get in people's hands, and we can see some numbers on it.

 

Absolutely. HTC are taking a U726 on the road with them so we will get some figures from them, plus we should be getting more info from our product management team on this and writing up some more details FAQs in the near future. Quite a few of our hardware partners and 3D devs have shown an interest in promoting the technology and it shouldn't be long before this is all available - expect from lots of other companies as well!

 

There is a larger than 4% difference between the 980M and 970 desktop, you can run the specs on both to show that.

980m = 1536 shaders at a boost clock of 1127mhz, 1250mhz 256 bit GDDR5
970 = 1664 shaders at a boost clock of 1178mhz, 1750mhz 224 bit GDDR5

980m = 1536 x 1127 = 1731072 core, 1250x256 = 320,000 memory
970 = 1664 x 1178 = 1960192 core, 1750x224 = 392,000 memory

13.24% core performance difference
22.5% memory performance difference

Now there is a slight cache and ROP difference but I am also leaving out the fact that GPU boost 2.0 will be far more aggressive on the 970 desktop and this is a worst case scenario for the desktop GPU. The 970 will always do better than the rough numbers above.

4% is the difference in listed boost clocks, and the old adage you can't just look at listed clocks (especially with boost 2.0) certainly applies here.

 

okay but will I beable to use the Rift with my np9377sm-a? 980m sli?

 

If nvidia and the game developer support VR SLI sure. If not, you might have to dial back settings to maintain an acceptable framerate on one 980M.

 

Yes the rift does work through thunderbolt so you should be ok for actually getting it to output.

 

One must look at the fill rate or Texture Mapping Unit of the GPU to get an idea of the performance of any given chipset.
I made this spreadsheet to better understand the differences. The 980m is on par with the 970 with the 970 having a 10% greater fill rate..

In this I estimated the target resolution to be 2880x1600, and at 90hz approximately 400 million pixels per second. The 980m has a theoretical limit of 1100 million pixels per second. So in practice and using nVidia Multi Resolution Shading.. The Oculus running at the recommended frame rate will use a little less than a third of the total theoretical fill rate.

However once you also calculate the overhead of a modern deferred Shading engine with up to 7 buffers forming the final composited frame ( total buffer count do vary ) and then on top of that any physics also being handled by the same GPU then very quickly does it become apparent why the minimum recommended specs by Oculus are brutally lofty!

Anyhow I would recommend you guys don't tell your customers that the 980m is up for the cut.. There are some incredibly resource hungry games out there that already slap mobile gaming in the face.. Combine this the resource demands of the Oculus then you quite possibly will have something unplayable..

In the VR world frame rate is king so to sell this the consumer will have to accept running games at lower quality settings than what they might be expecting..

 

I was using the minimum advertised boost clock for my calculations, since the TMUs and shaders are in the same proportions (being part of the same block) that's the only reason my maths does not match yours, the GPU clock gap you have between the 980M and 970 will never exist.

The 970 in games stays around the 1200mhz mark with factory overclocked cards around the 1300-1350mhz mark.

 

@Meaker.. all good bro! certainly an interesting thread going on here.. I've deemed it an important research topic.. The real cool stuff about VR is not just the tech.. it's the ideas of embodiment in VR applications.. this stuff is what is gonna change the world..

 

It's a great thing that the latest models have added in the switchable graphics (NP8657/P650RE) and up will at the very least be able to hook it up and run it in some form or another.

It certainly gives tweakers more excuse than ever (not that they tend to need one anyway )

Hopefully it does give SLI/Xfire the shot in the arm needed and makes some more interesting designs pop up with better interconnects to let it happen more easily.