VGA, HDMI, USB and other mess
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I have had a problem: I bought a GPD Pocket 2 computer for my wife.
It's a tiny (7") notebook but it is powerful enough to be used also as
a desktop (Core m5 CPU, 8GB of RAM, 128GB eMMC). Unlike the original
GPD pocket it does not have any HDMI output. The manufacturer states
that it is not necessary because it has an USB-C port which supports
the Thunderbold (or what it is called) and thus which can be used to
connect an external screen.
I initially thought that I can my USB-to-VGA card (with a SiS chipset)
which is known to work with Linux (if work with my Sharp NetWalker, for
example). The Pocket 2 has 2 full-size USB ports. But it is not so
easy: by default the modern Ubuntu ignores it. One had to set up an
xorg.conf (I have it for my NetWalker so if should be possible) and
there are also other problems like strange resolutions.
So I abandoned this idea and reserved this cart for the NetWalker. Then
I tried a USB-C adapter for VGA. It worked well except the fact that if
I turned off the build-in screen then the external resolution was
changed to something like 640x480 and I was not able to fix it. There
is another problem: the USB-C port is used for charging. If one puts
VGA adapter there then there is no way to charge device. So this is OK
for presentations but not for desktop use.
My next idea was to find an USB-C hub. But I had no luck: there is
nothing which has more than 2 USB-C ports and these ports usually
cannot be used for video signal.
So I have got a I-Tec USB-C hub which has 2 USB ports, two USB-C ports
(one of them supports charging), one full-size HDMI and one Ethernet
port. The "normal" USBs work, the Ethernet and the USB-C for charging
work, too. But no one USB-C can be used to connect and VGA adapter. So
I put my Lenovo HDMI-to-VGA adapter to the HDMI port. It worked, even
with the Ubuntu. But it worked in the same way as the USB-C to VGA
adapter - if both screens (and external and the internal) were on the
everything was OK. When I turned the internal screen off the external
one became unusable.
So the last try has been a HDMI-DVI adapter. And have been working!
The only problem is that I have to use the adapter and the HDMI cable
from my ODroid computer (I have spare ones elsewhere but I'm not able
to find them at the moment...).
I understand that it is hard to make stuff compatible with the analog
VGA thing. But I cannot get why it is so hard to get an USB-C hub...
Resume: my wife now has a workstation based on a GPD Pocket 2. And for
presentations she has an USB-C to VGA adapter. So she no longer needs
one computer for desktop work and second one (the Asus Eee 901) for
presentations. Ghat's great. But the solution was somewhat complicated.
P.S. This post was created on my trusty SGI O2 computer with the 1600SW
LCD. There was no VGA, DVI, HDMI or USB thing involved is the writing.
Just to be sure that there will be no surprise.