[RndTbl] How Long Can HDMI Cable be Run? -- Blue Jeans Cable

Trevor Cordes trevor at tecnopolis.ca
Wed Sep 9 01:13:26 CDT 2015

Some more research:

"1.4 spec, in order for an HDMI cable to be considered high-speed, it
must be able to pass 3,840x2,160 pixels at up to 30 frames per second
(and 4,096x2,160 at 24 frames per second)."

Using my math-fu that means that the bandwidth that 3840x2160 at 30 the
above says 1.4 can do is MORE than the bw the Dell 2560x1440 at 60
requires, meaning that a HDMI 1.4 cable should drive the Dell.  I'll
make sure I obtain a (non-liar) 1.4 cable to test next.  Maybe a 6 and
a 12, to ensure length isn't a factor.

It's surprising that there's a dearth of info on this stuff on the
net.  For instance, most video card spec pages (for >1 year old cards
at least) don't list the HDMI version supported.  I don't think there's
a (linux) software way to tell either.

There are ton of people trying to attach 2k and 4k monitors to their
existing cards with DVI/HDMI and running into problems.

This seems to be bleeding edge, no info out there, you're on your own
territory.  I'm a bit annoyed since I'm not even trying to do 4k, just
lousy 2k that even 10 year old DVI supports!  Grrr.

P.S. The reason I didn't just use DVI is that the new monitor has no
DVI!  P.P.S. DVI can support 2560x1440 as long as it's dual-link.

The other real gotcha for me is that my workstation is older and many
newer PCI-express cards I try don't run in it (no POST).  I've seen
this with many older boards, not just mine.  It's all supposed to be
backwards compatible, but in reality it is not.  So if I buy a new card
with d.port I'd say there's a 75% chance it won't work for me.  I would
buy a new board too, but my ws is ECC and that means $1k+, not $400 for
a guts upgrade.  Higher rez isn't worth $1k + monitor price to me: not
yet anyway.  :-)

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