A warning for any A/V pros looking at Lenovo laptop products in hopes to use them for video play-out!
Hello my name is Greg Meisel owner of #ifelseWare, Inc. (https://ifelseware.com) and developer of the #AV-Playback line of of professional video play-out solutions. I am fully aware that I will probably get quite a bit of flack for what I am about to write, but this is a serious enough problem I feel you all need to know before making an expensive purchase.
The short version is… If any of you are thinking about purchasing a new PC laptop for the purpose of video playout in a professional environment… Stay far far away from any Lenovo brand units!
Now for the long version… Over the last couple of years, I have received several tech support issues related to Lenovo products. At first, it seemed to only be with the “Think Pad” line they acquired from IBM. Now at that time, it showed up as a problem when trying to use certain video renders. The issue was it could not share a video stream between the Nvidia GPU and the ubiquitous integrated Intel GPU. AV-Playback needs this to be possible in order that you can have a program confidence monitor within the operator’s view. Back then I did post a warning, however, to my disappointment, people still purchased them, and the complaints continued (Needles to say, they would simply blame the software.) In this scenario, I just brushed it off to the fact those earlier models were equipped with only the “M” series chips, which are basically just a graphics co-processor that has few CUDA threads plus a small amount of dedicated memory. However, after talking with a friend at Nvidia I found out that Lenovo was doing some sort of internal loopback of the data flow between the integrated Intel GPU and the extended Nvidia GPU. Thankfully this issue was settled once I totally rebuilt the video engines and included them into the release of version V2 and L1.
OK, now let’s fast forward to today. To our dismay, many have found that even all of their new offerings still have a problem, even their Legion gaming machine. This time though, it seems to be manifesting in a different way. The new issue is anytime a new clip is loaded and then played for the first time, frame one will appear but then stalls briefly, glitches, and then finally begins to play properly. I believe this new issue is in some way related to the old one. I found that they are still doing this funky loopback through the two separate GPUs.
By the way, so far only Lenovo appears to design their systems this way. Most simply direct the output of the high-performance GPU straight to the external outputs and leave the internal display and all USB outputs to the Intel chip. They realize that if you are a serious gamer (or in our case large event video playback) you are going to want a much larger external display or projector anyways. We and our customers have tested many other brands and have found that they do not appear to suffer from this problem.
In our own deep testing of both a fresh new ThinkPad as well as a Legion gaming model, we found that the issue is due to how they go about integrating the Nvidia GPU chip into their motherboard design. Now, I admit I do not have direct knowledge as to how their systems are designed and I am guessing at what is going on here but I believe it's a good educated guess... It appears their overall objective maybe to employ the Nvidia chip to enhance graphic ability in the laptop’s own display screen. At first you may think “That’s Great!”, better gaming and 3D rendering performance. The problem, however, is in order for that output to be realized on the laptop display, it needs to routed somehow through the motherboards LVDS connector, (Note: These ports are commonly used by all laptop manufactures and makes assembly convenient.) The thing is, architecturally those connectors are linked directly to the embedded Intel chipset and GPU. In order to get the Nvidia chip to crunch the numbers and get its results to the laptop display, they apparently need to loop the Nvidia output directly into the Intel’s input and then have it distribute between the internal display and all other outputs. Here is where the problem seems to begin. This act causes either the Intel or Nvidia chip to stall every time a new bitstream is ported through it. I theorize it may be due to the lack of a large enough memory cache on the Intel GPU, so when the much larger video stream comes down the pike from the Nvidia chip. It first has to catch its breath and then ask the system to allocate more ram memory for its use, since the Intel chip has now real dedicated memory and in the bios you can only preallocate up to 512MB or ram. During this moment our video stream has briefly stalled, and of course, looks terrible on screen. Now once the new thread allocation is established there are no more problems. You can stop-start the video and no longer see any glitches. But let's think about this, when do you ever have a show where you were only playing one video… Probably never. Instead we need to jump from one clip to another, numinous times, but once a clip is removed from the buffer and then replaced, a whole new thread has to be allocated and the same ugly problem occurs when the new clip is first played. In many other situations like game play this issue is not as noticed. Seeing that not only does most games render directly to the GPU, but once the game is launched all allocated threads will remain in tact for as long as the game is active. It only seems to appear when multiple video files are constantly loaded and unloaded, removing and relocating threads, do we really notice this issue.
You may be thinking at this point “It must be a problem with your software”, well, we and others have tried a few other pieces of Windows-based playback software, and we still see the same issue occur in their output as well.
NOTE: We tried disabling the Nvidia chip in the bios and miraculously the problem went away. However, since the Intel chip has to little memory it begins to choke on high resolution video files (1080p and above.) A real catch 22!
In conclusion, I still have to wonder why it is even necessary to have the weaker integrated GPU. Companies like Lenovo are custom manufacturing their motherboards anyways, so instead, why can't they simply design them to only have one much more powerful Nvidia GPU and forgo the Intel chip altogether? I know it's possible because all of our rack systems are built that way.
I’m sorry to those out there that may love their Lenovo products. I even admit, in many ways, they are nice computers. However I must say... STAY AWAY FROM THEM IF YOU ARE WANTING TO USE IT FOR ANY MISSION-CRITICAL VIDEO PLAYBACK. At least until this problem is resolved.
As always have a great show!
ATTENTION: If anyone from Lenovo reads this and is concerned with my comments please let us talk together about it. Perhaps you may already know a way to cure this and can share or maybe your engineers might be able to come up with a solution. Either way you can email me directly at [email protected].