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Since Google has been worse than useless so far, I figure I'd see what people here know...

Recently, I ordered a Type C adapter that breaks out to a Type C, DVI, and Type A. (http://www.monoprice.com/product?c_id=1 ... 1&format=2) Upon malfunction, I tested it on another computer: an Acer Switch 12 which has worked with that specific item as well as a Type C to VGA dongle.

Neither dongles work on the ASUS GL502VS. The Monoprice dongle's USB works momentarily with mice and keyboards, then stops once Windows 10 "installs the driver". The Acer Switch 12 doesn't do any of this behavior and everything seems to be working properly. The problems occur regardless of what I have already hooked up to the laptop's HDMI and Mini-DP, or if I have nothing connected at all.

Is there a defect in the Type C port? Problem with the BIOS? Missing driver? Windows 10 itself? Or did ASUS not follow the spec? Curious here if anyone's run into this issue.

Edit: Turns out the spec is a f***ing mess right now. The laptop didn't even list the port's capabilities in the spec sheet.

http://blog.fosketts.net/2016/10/29/tot ... derbolt-3/

Anyway, I guess this can be a ranting topic for now? Unless others know what's going on and could chime in, that'd be nice.

C-A_99 wrote:

Since Google has been worse than useless so far, I figure I'd see what people here know...

Recently, I ordered a Type C adapter that breaks out to a Type C, DVI, and Type A. (http://www.monoprice.com/product?c_id=1 ... 1&format=2) Upon malfunction, I tested it on another computer: an Acer Switch 12 which has worked with that specific item as well as a Type C to VGA dongle.

Neither dongles work on the ASUS GL502VS. The Monoprice dongle's USB works momentarily with mice and keyboards, then stops once Windows 10 "installs the driver". The Acer Switch 12 doesn't do any of this behavior and everything seems to be working properly. The problems occur regardless of what I have already hooked up to the laptop's HDMI and Mini-DP, or if I have nothing connected at all.

Is there a defect in the Type C port? Problem with the BIOS? Missing driver? Windows 10 itself? Or did ASUS not follow the spec? Curious here if anyone's run into this issue.

The Type-C port on the Asus GL502VS doesn't support any Type-C alternate modes from browsing through the manual. The good news is that if you want DVI, you can use a simple HDMI-to-DVI adapter (note that you're limited to 1920 x 1200 maximum resolution).

You can attach more than two displays to that Asus laptop but you'd need a DP MST hub ike this to break out the miniDP port. You are still limited by the GPU for maximum monitor support, which is 4 with nVidia and 3 with Intel. The laptop's screen counts toward those maximums.

C-A_99 wrote:

Edit: Turns out the spec is a f***ing mess right now. The laptop didn't even list the port's capabilities in the spec sheet.

http://blog.fosketts.net/2016/10/29/tot ... derbolt-3/

There are a couple of things wrong on that page and is omitting a few more edge cases. The main point of that page though, that USB-C is a mess, is absolutely correct.

That article never really pointed out that by spec, all Thunderbolt 3 host devices also support the USB Type-C DP alternate mode. So if you have a Thunderbolt 3 port, you can use a USB Type-C to DP adapter to get video. DP spec permitted by Thunderbolt 3 is limited to DP 1.2 speeds however but Thunderbolt 3 can encapsulate two independent DP 1.2 data streams. This matters when driving 5K displays as the display itself has to be Thunderbolt 3 enabled to drive it full resolution and refresh as the two DP 1.2 streams have to be combined inside of the display.

The article is incorrect about the maximum resolution the DP alternate mode can support. Using DP 1.3, the DP alternate mode can drive a 5K display or two 4K displays with a DP 1.3 MST hub. The catch is that there are no devices on the market that mix both USB Type-C and DP 1.3. Those are coming in 2017 to add even more confusion. So for today, if you see a USB Type-C port capable of driving a 5K display, that port has to Thunderbolt 3 compliant and uses the tricks listed above to do 5K.

Oddly enough, active cabling for Thunderbolt 3 is not required but you'll be limited to 20 Gbit speeds. Essentially you can use a USB Type C 3.1 Gen 1/2 cable and get 20 Gbit Thunderbolt. There are no special 20 Gbit Thunderbolt 3 cables. Active cabling is required to reach 40 Gbit Thunderbolt 3. The 40 Gbit/s active cabling for Thunderbolt 3 can also be used for the other USB speeds and devices.

There is no difference in cabling between USB Type-C 3.1 Gen 1 and USB Type-C 3.1 Gen 2 to get the higher data rate. The catch is that in the examples lists there is also a difference between the maximum amount of power provided over that cable. Going from 15W to 100W does invoke a difference in cabling. Changing from 5 Gbit to 10 Gbit by itself can utilize the same cable.

There are no devices on the market (yet) that use the true HDMI alternate mode provided by USB Type-C. This is because it was only officially ratified a few months ago. So why are here USB Type-C to HDMI adapters on the market a year before that? The reality is that those adapters are either using an active DP to HDMI conversion chip or utilizing MHL over an HDMI connector. This is due to DP and MHL both having official alternate modes. This is also where the idea that USB Type-C only supports HDMI 1.4 comes from as that is the limit of the official HDMI alternate mode. However, HDMI 2.0 can be done via an active DP 1.2/1.3 to HDMI 2.0 conversion (see here for an example).

Speaking of conversion, that article is incorrect about Thunderbolt 3 supporting HDMI 2.0. Technically speaking, it does not. Rather, Thunderbolt 3 is just demux a DP stream and then it is converted as mentioned above.

Even vanilla USB3 has weird issues as late as Haswell. My USB3 Wi-Fi adapter in USB2 mode is actually faster and far more stable on either Asmedia or Intel USB3 ports. I don't even want to dabble in the mess called Thunderbolt or X over Type-C.

the wrote:

<many words>
The main point of that page though, that USB-C is a mess, is absolutely correct.
<many more words>

I have no devices yet that have a USB-C port. Reading this, I'm not sure I ever want to. This makes it sound like it was designed by marketing executives, not engineers.

strangerguy wrote:

Even vanilla USB3 has weird issues as late as Haswell. My USB3 Wi-Fi adapter in USB2 mode is actually faster and far more stable on either Asmedia or Intel USB3 ports. I don't even want to dabble in the mess called Thunderbolt or X over Type-C.

Gee, and here I've been blaming my USB3 woes on the lack of native support on the Socket AM3+ platform, and the fact that I'm running Linux. I guess it is a small consolation that users of Windows on Intel have issues too?

the, thanks a ton for that post and for clarifying the misinformation in the article.

I was off-put by the idea of using a DP hub due to the lack of monitor independence (or so a salesperson at Micro Center said), but was not aware of the MST standard. I'm basically trying to run 3 1080p screens (which was my standard on the desktop before I got the new laptop), but if the cost just to connect them stacks up too high, I'll have to consider other options. Still, at this point, I prefer more screens over larger ones.

MST hubs are great as they enable truly independent monitors.

I didn't see it mentioned in the Asus manual which GPU drives the miniDP port. The system could be using an Optimus arrangement where the displays are driven by the Intel chip but the real 3D work is done on the nVidia GPU. Thankfully the nVidia control panel will tell you which display is connected to what GPU if it is using Optimus.

The MST hubs on the market today are all DP 1.2 based and DP 1.3 hubs are due next year. If that miniDP port comes off of the nVidia GTX 1070, then you'd have DP 1.3 support. What a DP 1.3 hub get you is dual 4K or four 2560 x 1600 displays over a single connector. On the other hand the current DP 1.2 MST hubs can do two 2560 x 1600 or four 1080p displays.

I picked out a DP 1.2 MST hub; looks like I'm a year off on a potential price drop, but future proofing isn't that important yet until I get into higher res screens, which is not in my budget nor planning yet.

I don't think the laptop has Optimus. The Nvidia control panel doesn't show which graphics card is connected, and I haven't seen any Intel IGP control panel anywhere on the system. This makes things less troublesome; last time I had a laptop with switchable GPU's, the driver was locked to being unable to display proper HDMI color gamut and I'm not sure I'd trust them to sort the issue out. I'm not counting on using a computer like this on battery for very long though, so it's not too much of a concern for me.

Funnily enough, if the sales guy at Micro Center knew all this, they could've sold me the DP hub and an active DVI converter along with my laptop when I bought the thing Turns out it didn't make a difference, since I had to have it right now instead of waiting for it to ship from online.  I found that being able to use only 2/3 monitors on the desk is a very awkward experience.