[GTALUG] Intel GPU support for HDMI 2.0 (UltraHD)

[D. Hugh Redelmeier]

| From: Nicholas Krause via talk <talk at gtalug.org>

| If I recall HDMI 2.0 like USB 3.2 and PCI 4.0 does not require a hardware
| upgrade. The protocol changed but older hardware should use it depending
| on if it can handle the new requirements.

Not exactly.

HDMI 2.0 does not require new cables over HDMI 1.x.  The connectors
and signals are "the same".  But the bandwidth is higher so old cables
may well not work.  There is an optional certification system for cables.

HDMI 2.0 sources and sinks must support HDMI 1.x.  So when you hook up
an HDMI system, if either end is only 1.x, the result will be that a
1.x signal will be used.

If you want UltraHD @ 60 Hz, you need HDMI 2.0 on both sides and a
cable that can handle the bandwidth.

| This was one of the reasons
| AMD did allow for awhile, PCI 4.0 on older Ryzen chipsets.

That's not how I understand it.

This generation of Ryzen CPUs support PCI 4.0.
Certain Ryzen support chips can support PCI 4.0, even those on
motherboards that predate Ryzens CPUs that support PCI 4.0.

So: you could buy an older Ryzen motherboard and plug in a current
Ryzen chip, and get PCI 4.0.

But: those motherboards were probably not tested/qualified for PCI
4.0.  They might not be reliable.  So AMD sent out a firmware update
to disable PCI 4.0 on those motherboards.

Alternate explanation: those motherboards were cheap.  AMD wanted to
steer PCI 4.0 customers to new motherboards with expensive support
chips.  The difference in price was about $100-$150, if I remember
correctly.

This, of course, upset customers that thought that they could get PCI
4.0 and had this taken away.

Luckily, hardly any consumer device is bottlenecked by PCI 3.x at the
moment.  In the future, GPUs and NVMe SSDs will be.

<https://www.tomshardware.com/news/amd-pcie-4.0-socket-am4-motherboard,39559.html>

| If HDMI for the last two versions is like this it really doesn't make sense
| to not allow it on certain older computers. Probably just a way for Intel
| to sell more chips maybe.

I don't think so.  The bandwidths of HDMI are really quite high.
Getting old chips to do it isn't likely a simple firmware upgrade.

Both HDMI 2.0 and PCI 4.0 probably consume more power.

I'm more annoyed at system manufacturers that didn't bother to include 
an LSPCON.  We have two Dell notebooks that don't have them: one low-end 
and another high-end (with an UltraHD built-in screen!).  Grrr.

The majority of our computers (way too many!) are Haswell and older 
because newer processors aren't good enough to obsolete Haswell.  But the 
GPU is a weak spot that even an LSPCON could not fix.