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All HDMI cables are not the same
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hon...@yahoo.com
Feb 14, 2015, 3:06:55 PM2/14/15
to
I just put together a new mini-desktop with HDMI connecting the monitor. Worked great, except for some reason the monitor would not go into power save when commanded by the computer. Instead a box bounced around on the screen saying there's no signal, going to sleep in 5 minutes.
It's not the worst thing I know, but I wanted to know why it did this. I did some research, and while the general consensus was "I have no idea why it does that, live with it", I found a forum post that claimed it was the HDMI cable itself. I have two TVs with HDMI cables each to a media player. One TV used the exact same cable, the other had a different, thicker cable. I stole the thicker one and guess what? Power save now works fine.
I can find HDMI pinouts easily enough, but nothing on how power save is commanded with HDMI. It seems to me the cheaper, thinner cables skimped by skipping a few connections. Unfortunately there's little info on any of this, but I have learned something:
Despite common wisdom, not all HDMI cables are the same. I just don't advise you buy this:
http://www.amazon.com/AudioQuest-Diamond-6-56-Braided-Cable/dp/B003CT2A2M
Even the cable that works cost me no more than a few bucks. The question now is, how to avoid buying the ones that aren't up to par?
It's not the worst thing I know, but I wanted to know why it did this. I did some research, and while the general consensus was "I have no idea why it does that, live with it", I found a forum post that claimed it was the HDMI cable itself. I have two TVs with HDMI cables each to a media player. One TV used the exact same cable, the other had a different, thicker cable. I stole the thicker one and guess what? Power save now works fine.
I can find HDMI pinouts easily enough, but nothing on how power save is commanded with HDMI. It seems to me the cheaper, thinner cables skimped by skipping a few connections. Unfortunately there's little info on any of this, but I have learned something:
Despite common wisdom, not all HDMI cables are the same. I just don't advise you buy this:
http://www.amazon.com/AudioQuest-Diamond-6-56-Braided-Cable/dp/B003CT2A2M
Even the cable that works cost me no more than a few bucks. The question now is, how to avoid buying the ones that aren't up to par?
Adrian Jansen
Feb 14, 2015, 8:21:51 PM2/14/15
to
Digital signals dont normally get 'lost' down a connection, regardless
of whether the wire is 'ordinary' or 'magic'.
--
Regards,
Adrian Jansen adrianjansen at internode dot on dot net
Note reply address is invalid, convert address above to machine form.
hon...@yahoo.com
Feb 14, 2015, 9:16:03 PM2/14/15
to
On Saturday, February 14, 2015 at 7:21:51 PM UTC-6, Adrian Jansen wrote:
>
> So why dont you just do a pin-to-pin connectivity check ?
>
> Digital signals dont normally get 'lost' down a connection, regardless
> of whether the wire is 'ordinary' or 'magic'.
>
> --
I thought about doing a conductivity check, but then didn't have the ambition. However a conductivity check isn't possible when the cable is on Ebay or Newegg.
>
> So why dont you just do a pin-to-pin connectivity check ?
>
> Digital signals dont normally get 'lost' down a connection, regardless
> of whether the wire is 'ordinary' or 'magic'.
>
> --
Jeff Liebermann
Feb 14, 2015, 10:50:03 PM2/14/15
to
On Sat, 14 Feb 2015 12:06:51 -0800 (PST), hon...@yahoo.com wrote:
>I just put together a new mini-desktop with HDMI connecting the monitor.
Good timing. I just dragged home a somewhat faster machine for
>I just put together a new mini-desktop with HDMI connecting the monitor.
myself. I'm in the computer repair biz, so this should be a no
brainer. The machine has a video card with an HDMI output and my
Flatron L246P also has a matching HDMI input. What could possibly go
wrong?
Well, the L246P has a resolution of 1600x1200. Maximum vertical
resolution for HDMI output on the video card is 1080 dots. Circles
look like ellipses and there's no way to adjust the aspect ratio. So
much for HDMI on a monitor that has too many dots. The HDMI specs go
to a much higher resolution:
<http://en.wikipedia.org/wiki/HDMI#Version_comparison>
but apparently the video card maker didn't read the spec.
So, I went back to the old 15 pin D-connector, and grumbled happily
thereafter.
>I have two TVs with HDMI cables each to a media player. One TV used
>the exact same cable, the other had a different, thicker cable.
>I stole the thicker one and guess what? Power save now works fine.
1.0, 1.1, 1.2, 1.3, 1.4, and now 2.0 ??
It shouldn't have any effect on the problem, but I'm curious.
>I can find HDMI pinouts easily enough, but nothing on how power
>save is commanded with HDMI. It seems to me the cheaper, thinner
>cables skimped by skipping a few connections. Unfortunately there's
>little info on any of this,
skimmed the specs and found nothing:
<http://www.hdmi.org>
<http://en.wikipedia.org/wiki/HDMI>
However, I did look at several (printed) schematics and found that
power save mode is initiated by the lack of video signals or data
depending on the input connector. In other words, it's up to the
monitor to shut itself down when there's nothing to look at.
I haven't seen this effect before, but then I don't sell many HDMI
cables. My best guess(tm) is that one wire from a differential data
pair came loose or wasn't soldered. The intact wire is picking up
hummmm and digital junk from the other wires in the bundle, which is
what's keeping the display on. That should show up with an HDMI
continuity tester:
<http://www.ebay.com/sch/i.html?_nkw=hdmi+tester>
Incidentally, I ran into another HDMI cable problem. I was setting up
the lady friend's new Roku 3 player. I grabbed whatever HDMI cable
was closest to the top of the pile from my office and used it to feed
the big 50" TV. You can really see signal problems with a big TV and
this one had a picture that looked terrible. What to do?
My normal troubleshooting method was to repair by substitution,
starting with the easiest and cheapest. That's when I noticed the
rather thin and ultra flexible HDMI cable. Going out to the car and
digging for a much thicker and presumably better cable, I eventually
found one. It worked and the picture quality was much improved.
Moral: If the cable looks inadequate, it probably is.
>The question now is, how to avoid buying the ones that aren't up to par?
commodity stuff on eBay. Occasionally, I get something with a
problem. I email the vendor and ask for an exchange for something
that works. If it's really cheap, like commodity HDMI cables, they
just send me a new one, and not ask for the return of the defective
cable.
--
Jeff Liebermann je...@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
hon...@yahoo.com
Feb 15, 2015, 10:55:42 AM2/15/15
to
On Saturday, February 14, 2015 at 9:50:03 PM UTC-6, Jeff Liebermann wrote:
> On Sat, 14 Feb 2015 12:06:51 -0800 (PST), hondgm wrote:
Interestingly, I did notice that both HDMI cables said "HDMI" on one side of each connector. However the problematic one had nothing on the other side. The one that worked said "v1.3". So, maybe having no version number is a bad sign. Luckily in this case, that cable is connected to a TV which doesn't care about power save.
It's possible the bad HDMI cable had a wire off, however I can't help but to think that the super-cheap ones are cheap because they tried saving every milli-penny possible. This could mean leaving out the wire for power save, but which one and how that's done, yeah that's the mystery. One other attribute I noticed is the connector feels hollow, versus the better one with a connector that feels molded.
In any case, the suspect cable gives a perfect image on the 1920x1080 monitor, as well as on the TV when connected to a WD TV Live.
I just realized that the bad cable is one I got from Newegg for something like $1.50 shipped as some type of special. That's surprising because I usually assume Newegg sells decent stuff. (http://www.newegg.com/Product/Product.aspx?Item=N82E16882850010)
> On Sat, 14 Feb 2015 12:06:51 -0800 (PST), hondgm wrote:
Interestingly, I did notice that both HDMI cables said "HDMI" on one side of each connector. However the problematic one had nothing on the other side. The one that worked said "v1.3". So, maybe having no version number is a bad sign. Luckily in this case, that cable is connected to a TV which doesn't care about power save.
It's possible the bad HDMI cable had a wire off, however I can't help but to think that the super-cheap ones are cheap because they tried saving every milli-penny possible. This could mean leaving out the wire for power save, but which one and how that's done, yeah that's the mystery. One other attribute I noticed is the connector feels hollow, versus the better one with a connector that feels molded.
In any case, the suspect cable gives a perfect image on the 1920x1080 monitor, as well as on the TV when connected to a WD TV Live.
I just realized that the bad cable is one I got from Newegg for something like $1.50 shipped as some type of special. That's surprising because I usually assume Newegg sells decent stuff. (http://www.newegg.com/Product/Product.aspx?Item=N82E16882850010)
Jeff Liebermann
Feb 15, 2015, 12:08:06 PM2/15/15
to
On Sun, 15 Feb 2015 07:55:36 -0800 (PST), hon...@yahoo.com wrote:
>On Saturday, February 14, 2015 at 9:50:03 PM UTC-6, Jeff Liebermann wrote:
>> On Sat, 14 Feb 2015 12:06:51 -0800 (PST), hondgm wrote:
>
>Interestingly, I did notice that both HDMI cables said "HDMI"
>on one side of each connector.
The cable is suppose to have "HDMI 1.3" or something similar printed
>On Saturday, February 14, 2015 at 9:50:03 PM UTC-6, Jeff Liebermann wrote:
>> On Sat, 14 Feb 2015 12:06:51 -0800 (PST), hondgm wrote:
>
>Interestingly, I did notice that both HDMI cables said "HDMI"
>on one side of each connector.
on the cable, not the connector. If you're trying to do ethernet, 3D,
or 4K TV, you'll need HDMI 1.4 or 2.0. If your cable lacks a proper
version number, it's probably 1.2 which lacks the provisions for
automatic lip sync.
>However the problematic one had nothing on the other side. The one that
>worked said "v1.3".
way, just "v1.3" does not follow the HDMI spec for labeling the cable.
However, that's the "old" spec. This is what you're suppose to see on
the cable:
<http://www.hdmi.org/consumer/finding_right_cable.aspx>
I'll spare you my rant on what I think of such descriptive labels.
>I can't help but to think that the super-cheap ones are cheap because
>they tried saving every milli-penny possible.
or tested. At best, maybe sample tested. Caveat emptor and there's
no way you're going to get uniform quality at that price.
>This could mean leaving out the wire for power save, but which one
>and how that's done, yeah that's the mystery.
If they're absent, the monitor turns off.
>One other attribute I noticed is the connector feels hollow, versus
>the better one with a connector that feels molded.
likely the soldering in insulation displacement connection inside the
connector.
>In any case, the suspect cable gives a perfect image on the 1920x1080
>monitor, as well as on the TV when connected to a WD TV Live.
Live boxes, but don't use them. I switched to a Roku 2 XS. Much
better and faster than the WD.
>I just realized that the bad cable is one I got from Newegg for
>something like $1.50 shipped as some type of special. That's surprising
>because I usually assume Newegg sells decent stuff.
>(http://www.newegg.com/Product/Product.aspx?Item=N82E16882850010)
you had purchased several of these cables, and tested them all for
screen blanking. If only one failed to function properly, it's
obviously the cable. If they all failed, it might be a design or
construction problem.
I noted from the above URL photo that this cable is one of the thin
variety that gave me grief during the video quality problem on the
lady friends TV. Are you sure that the picture is good (in 1080p) and
that a thicker cable doesn't give a better picture? I couldn't see
much difference on my 25" TV, but the quality difference was horribly
obvious on a 50" TV in HD.
hon...@yahoo.com
Feb 15, 2015, 4:46:55 PM2/15/15
to
On Sunday, February 15, 2015 at 11:08:06 AM UTC-6, Jeff Liebermann wrote:
>
> >I can't help but to think that the super-cheap ones are cheap because
> >they tried saving every milli-penny possible.
>
> At $1.50/cable that's highly likely. I doubt that they were inspected
> or tested. At best, maybe sample tested. Caveat emptor and there's
> no way you're going to get uniform quality at that price.
>
> >This could mean leaving out the wire for power save, but which one
> >and how that's done, yeah that's the mystery.
>
> There is no power save wire. The display looks at the data signals.
> If they're absent, the monitor turns off.
>
That doesn't explain how the one wire wouldn't convey the desire to go into power save. If I simply unplug the HDMI cable from the monitor, it doesn't go into power save either. It does the same thing as with the "bad" cable: displays a message that there's no signal and it's going into power save in 5 minutes.
> >One other attribute I noticed is the connector feels hollow, versus
> >the better one with a connector that feels molded.
>
> I don't believe that the connector packaging is the problem. More
> likely the soldering in insulation displacement connection inside the
> connector.
>
> >In any case, the suspect cable gives a perfect image on the 1920x1080
> >monitor, as well as on the TV when connected to a WD TV Live.
>
> So much for my broken wire theory. Incidentally, I have several WD
> Live boxes, but don't use them. I switched to a Roku 2 XS. Much
> better and faster than the WD.
>
I use mine for playing files on my network drive as well as Netflix and Youtube. That limits me to the WD, although it doesn't have the best designed firmware.
> >I just realized that the bad cable is one I got from Newegg for
> >something like $1.50 shipped as some type of special. That's surprising
> >because I usually assume Newegg sells decent stuff.
> >(http://www.newegg.com/Product/Product.aspx?Item=N82E16882850010)
>
> Newegg does better than most. What would have been interesting is if
> you had purchased several of these cables, and tested them all for
> screen blanking. If only one failed to function properly, it's
> obviously the cable. If they all failed, it might be a design or
> construction problem.
I do actually have another on a different TV. I'll have to try that one sometime.
>
> I noted from the above URL photo that this cable is one of the thin
> variety that gave me grief during the video quality problem on the
> lady friends TV. Are you sure that the picture is good (in 1080p) and
> that a thicker cable doesn't give a better picture? I couldn't see
> much difference on my 25" TV, but the quality difference was horribly
> obvious on a 50" TV in HD.
>
>
The TV I swapped with was 19", and I have another one of those junky cables on a 32". What I can't understand is how the cable can cause bad image quality since it's a digital signal. Shouldn't it simply work or not?
> On Sun, 15 Feb 2015 07:55:36 -0800 (PST), hondgm wrote:
>
> >On Saturday, February 14, 2015 at 9:50:03 PM UTC-6, Jeff Liebermann wrote:
> >> On Sat, 14 Feb 2015 12:06:51 -0800 (PST), hondgm wrote:
> >
> >Interestingly, I did notice that both HDMI cables said "HDMI"
> >on one side of each connector.
>
> The cable is suppose to have "HDMI 1.3" or something similar printed
> on the cable, not the connector. If you're trying to do ethernet, 3D,
> or 4K TV, you'll need HDMI 1.4 or 2.0. If your cable lacks a proper
> version number, it's probably 1.2 which lacks the provisions for
> automatic lip sync.
>
> >However the problematic one had nothing on the other side. The one that
> >worked said "v1.3".
>
> Hopefully, you mean the side of the cable, not the connector. Either
> way, just "v1.3" does not follow the HDMI spec for labeling the cable.
> However, that's the "old" spec. This is what you're suppose to see on
> the cable:
> <http://www.hdmi.org/consumer/finding_right_cable.aspx>
> I'll spare you my rant on what I think of such descriptive labels.
Just looked at both cables. The junky one says "high speed HDMI cable" and the good one says "vw-1 HDMI cable" along with temperature and UL information in both cases. No mention of version.
>
> >On Saturday, February 14, 2015 at 9:50:03 PM UTC-6, Jeff Liebermann wrote:
> >> On Sat, 14 Feb 2015 12:06:51 -0800 (PST), hondgm wrote:
> >
> >Interestingly, I did notice that both HDMI cables said "HDMI"
> >on one side of each connector.
>
> The cable is suppose to have "HDMI 1.3" or something similar printed
> on the cable, not the connector. If you're trying to do ethernet, 3D,
> or 4K TV, you'll need HDMI 1.4 or 2.0. If your cable lacks a proper
> version number, it's probably 1.2 which lacks the provisions for
> automatic lip sync.
>
> >However the problematic one had nothing on the other side. The one that
> >worked said "v1.3".
>
> Hopefully, you mean the side of the cable, not the connector. Either
> way, just "v1.3" does not follow the HDMI spec for labeling the cable.
> However, that's the "old" spec. This is what you're suppose to see on
> the cable:
> <http://www.hdmi.org/consumer/finding_right_cable.aspx>
> I'll spare you my rant on what I think of such descriptive labels.
>
> >I can't help but to think that the super-cheap ones are cheap because
> >they tried saving every milli-penny possible.
>
> At $1.50/cable that's highly likely. I doubt that they were inspected
> or tested. At best, maybe sample tested. Caveat emptor and there's
> no way you're going to get uniform quality at that price.
>
> >This could mean leaving out the wire for power save, but which one
> >and how that's done, yeah that's the mystery.
>
> There is no power save wire. The display looks at the data signals.
> If they're absent, the monitor turns off.
>
> >One other attribute I noticed is the connector feels hollow, versus
> >the better one with a connector that feels molded.
>
> I don't believe that the connector packaging is the problem. More
> likely the soldering in insulation displacement connection inside the
> connector.
>
> >In any case, the suspect cable gives a perfect image on the 1920x1080
> >monitor, as well as on the TV when connected to a WD TV Live.
>
> So much for my broken wire theory. Incidentally, I have several WD
> Live boxes, but don't use them. I switched to a Roku 2 XS. Much
> better and faster than the WD.
>
> >I just realized that the bad cable is one I got from Newegg for
> >something like $1.50 shipped as some type of special. That's surprising
> >because I usually assume Newegg sells decent stuff.
> >(http://www.newegg.com/Product/Product.aspx?Item=N82E16882850010)
>
> Newegg does better than most. What would have been interesting is if
> you had purchased several of these cables, and tested them all for
> screen blanking. If only one failed to function properly, it's
> obviously the cable. If they all failed, it might be a design or
> construction problem.
>
> I noted from the above URL photo that this cable is one of the thin
> variety that gave me grief during the video quality problem on the
> lady friends TV. Are you sure that the picture is good (in 1080p) and
> that a thicker cable doesn't give a better picture? I couldn't see
> much difference on my 25" TV, but the quality difference was horribly
> obvious on a 50" TV in HD.
>
>
Jeff Liebermann
Feb 15, 2015, 5:37:42 PM2/15/15
to
On Sun, 15 Feb 2015 13:46:50 -0800 (PST), hon...@yahoo.com wrote:
>> <http://www.hdmi.org/consumer/finding_right_cable.aspx>
>Just looked at both cables. The junky one says "high speed HDMI cable" and
>the good one says "vw-1 HDMI cable" along with temperature and UL information
>in both cases. No mention of version.
Which means that you don't have a clue as to the capabilities of the
cable or to which HDMI version it complies. Swell.
The VW-1 means it will pass a "vertical wire" flame test per UL 1581:
<http://www.digikey.com/Web%20Export/Supplier%20Content/Techflex_1030/PDF/techflex-arc_VW1.pdf>
The complete markings on one of my HDMI cables from my pile is:
"HIGH SPEED HDMI CABLE WITH ETHERNET E119932-T AWM STYLE 20276 80C 30V
VW-1 COPARTNER".
>That doesn't explain how the one wire wouldn't convey the desire to go into
>power save.
An unbalanced pair of wires does not pickup any garbage from adjacent
wires (common mode rejection). However, if you break a wire, it will
act much like an antenna and pickup all kinds of crud.
>If I simply unplug the HDMI cable from the monitor, it doesn't go into
>power save either.
Unplugging the entire cable unplug both wires in the pair. That's not
a good test.
>It does the same thing as with the "bad" cable: displays a message
>that there's no signal and it's going into power save in 5 minutes.
If that's true, then I would look for something wrong with the
monitor, not the cable. Borrow another cable and try for 2 out 3
cables? If a 3rd cable does the same thing, then it's likely that the
problem is NOT in the cable.
>> I noted from the above URL photo that this cable is one of the thin
>> variety that gave me grief during the video quality problem on the
>> lady friends TV. Are you sure that the picture is good (in 1080p) and
>> that a thicker cable doesn't give a better picture? I couldn't see
>> much difference on my 25" TV, but the quality difference was horribly
>> obvious on a 50" TV in HD.
>The TV I swapped with was 19", and I have another one of those junky
>cables on a 32".
You won't see any difference on a 19" TV, which is probably limited to
720p. You should see a difference on the 32" in 1080p.
>What I can't understand is how the cable can cause bad image quality
>since it's a digital signal. Shouldn't it simply work or not?
The cable has a limited frequency response depending on which HDMI
mutation. Higher numbers mean more bandwidth. More bandwidth means
better resolution. In my case, the picture detail was not very sharp.
<http://en.wikipedia.org/wiki/HDMI#Version_comparison>
Note the range for frequencies for pixel clock rate, TMDS, and
throughput for the different HDMI mutations.
>> <http://www.hdmi.org/consumer/finding_right_cable.aspx>
>Just looked at both cables. The junky one says "high speed HDMI cable" and
>the good one says "vw-1 HDMI cable" along with temperature and UL information
>in both cases. No mention of version.
cable or to which HDMI version it complies. Swell.
The VW-1 means it will pass a "vertical wire" flame test per UL 1581:
<http://www.digikey.com/Web%20Export/Supplier%20Content/Techflex_1030/PDF/techflex-arc_VW1.pdf>
The complete markings on one of my HDMI cables from my pile is:
"HIGH SPEED HDMI CABLE WITH ETHERNET E119932-T AWM STYLE 20276 80C 30V
VW-1 COPARTNER".
>That doesn't explain how the one wire wouldn't convey the desire to go into
>power save.
wires (common mode rejection). However, if you break a wire, it will
act much like an antenna and pickup all kinds of crud.
>If I simply unplug the HDMI cable from the monitor, it doesn't go into
>power save either.
a good test.
>It does the same thing as with the "bad" cable: displays a message
>that there's no signal and it's going into power save in 5 minutes.
monitor, not the cable. Borrow another cable and try for 2 out 3
cables? If a 3rd cable does the same thing, then it's likely that the
problem is NOT in the cable.
>> I noted from the above URL photo that this cable is one of the thin
>> variety that gave me grief during the video quality problem on the
>> lady friends TV. Are you sure that the picture is good (in 1080p) and
>> that a thicker cable doesn't give a better picture? I couldn't see
>> much difference on my 25" TV, but the quality difference was horribly
>> obvious on a 50" TV in HD.
>The TV I swapped with was 19", and I have another one of those junky
>cables on a 32".
720p. You should see a difference on the 32" in 1080p.
>What I can't understand is how the cable can cause bad image quality
>since it's a digital signal. Shouldn't it simply work or not?
mutation. Higher numbers mean more bandwidth. More bandwidth means
better resolution. In my case, the picture detail was not very sharp.
<http://en.wikipedia.org/wiki/HDMI#Version_comparison>
Note the range for frequencies for pixel clock rate, TMDS, and
throughput for the different HDMI mutations.
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