News DisplayPort vs. HDMI: Which Is Better For Gaming?

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CerianK

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Another big issue for me is input switching latency when I flip between sources, which is something missing from product specifications and reviews (unless I've somehow missed seeing it).

I know that HDMI can be very slow (depending on monitor)... sometimes as much as 5 seconds to see the new source. I assumed that was content protection built into the standard and/or slow decoder ASIC.
I have not compared switch latency to Display Port, so would be curious if anyone here has impressions
.
Honestly, I would probably pay quite a bit extra for a monitor and/or TV that has much faster input source switching.. I have lost patience for technology regression as I have aged... I recall using monitors and TVs that had nearly instantaneous source switching back in the analog days.
 
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Another big issue for me is input switching latency when I flip between sources, which is something missing from product specifications and reviews (unless I've somehow missed seeing it).

I know that HDMI can be very slow (depending on monitor)... sometimes as much as 5 seconds to see the new source. I assumed that was content protection built into the standard and/or slow decoder ASIC.
I have not compared switch latency to Display Port, so would be curious if anyone here has impressions
.
Honestly, I would probably pay quite a bit extra for a monitor and/or TV that has much faster input source switching.. I have lost patience for technology regression as I have aged... I recall using monitors and TVs that had nearly instantaneous source switching back in the analog days.
My experience is that it's more the monitor than the input. I've had monitors that take as long as 10 seconds to switch to a signal (or even turn on in the first place), and I've had others that switch in a second or less. I'm not sure if it's just poor firmware, or a cheap scaler, or something else.

I will say that I have an Acer XB280HK 4K60 G-Sync display that only has a single DisplayPort input, and it powers up or wakes from sleep almost instantly. I have an Acer G-Sync Ultimate 4K 144Hz HDR display meanwhile that takes about 7 seconds to wake from sleep. Rather annoying.
 

bit_user

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My experience is that it's more the monitor than the input. I've had monitors that take as long as 10 seconds to switch to a signal (or even turn on in the first place), and I've had others that switch in a second or less. I'm not sure if it's just poor firmware, or a cheap scaler, or something else.
I always figured it's to do with HDMI's handshaking and auto-negotiation.

HDMI was designed for home theater, where you could have the signal pass through a receiver or splitter. Not only do you need to negotiate resolution, refresh rate, colorspace, bit-depth, link speed, ancillary & back-channel data, but also higher-level parameters like audio delay. So, probably just a poor implementation of that process, running on some dog-slow embedded processor.

As such, you might find that locking down the configuration range of the source can speed things up, a bit.
 

waltc3

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I'm surprised the article didn't mention TVs, as currently that's the main reason people go HDMI instead of DP, imo. I appreciated the fact that the article mentioned the loss of color fidelity the 144Hz compromise forces, although most people seem to ignore that difference. I include a link below that is informative on that topic--it's not mine but I saved the link to remind me...;) I haven't looked in a while, but last time I checked few if any TVs feature Display Ports--my TV at home is strictly HDMI. Personally, I use an AMD 50th Ann Ed 5700XT with a 1.4 DP cable plugged into my DP 1.4 monitor, the Ben Q 3270U.

View: https://www.reddit.com/r/hardware/comments/8rlf2z/psa_4k_144_hz_monitors_use_chroma_subsampling_for/
 

margrave

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This is really ho-hum. I only moved from VGA to HDMI when the new desktop had a GPU that allowed it.
Aside from that ... no difference. I had no flickering or noise with VGA. It worked perfectly. The HDMI is no better.
Once again ... ho-hum.
 
I'm surprised the article didn't mention TVs, as currently that's the main reason people go HDMI instead of DP, imo. I appreciated the fact that the article mentioned the loss of color fidelity the 144Hz compromise forces, although most people seem to ignore that difference. I include a link below that is informative on that topic--it's not mine but I saved the link to remind me...;) I haven't looked in a while, but last time I checked few if any TVs feature Display Ports--my TV at home is strictly HDMI. Personally, I use an AMD 50th Ann Ed 5700XT with a 1.4 DP cable plugged into my DP 1.4 monitor, the Ben Q 3270U.

View: https://www.reddit.com/r/hardware/comments/8rlf2z/psa_4k_144_hz_monitors_use_chroma_subsampling_for/
Erm ... I mention TVs probably ten times if you check, including a note near the end about how TVs generally require the use of HDMI (BFGDs being the sole exception I'm aware of). I typically run my Acer 4K 144 Hz HDR at 4K 98 Hz just so I can get full RGB, though -- that's something HDMI 2.1 and DP 2.0 will address.
 
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waltc3

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Erm ... I mention TVs probably ten times if you check, including a note near the end about how TVs generally require the use of HDMI (BFGDs being the sole exception I'm aware of). I typically run my Acer 4K 144 Hz HDR at 4K 98 Hz just so I can get full RGB, though -- that's something HDMI 2.1 and DP 2.0 will address.

Maybe I'm going blind in my dotage--somehow didn't see it...;) I'm sure you are correct and I stand corrected.
 
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CerianK

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TVs are a funny topic for me... I could write a research paper on getting my Sony 49" 4K TV to do 1080p@120Hz without dropping a frame every 5 seconds over Display Port to active HDMI converter. Not a cable issue and it was hardly noticeable most of the time while gaming, but I could tell sometimes, so wrote a B/W gating app to study it. I was eventually able to figure out that I had to bias high to about 120.3Hz to negate the issue. Nvidia 1060, BTW.

I wouldn't be surprised if there is a 'restricted distribution' paper written for Sony internal use which documents the entire setup process... you wouldn't want just anyone to be able to pay TV prices to obtain the equivalent of a giant high Hz gaming monitor.

The time I spent on that issue cut into my Doom play time (using Vulkan API), the reason I bought the TV. Oddly, I spent way more time playing it on 4K@60Hz, just because, well, 4K is sweeter than 1080p at that screen size.
 
TVs are a funny topic for me... I could write a research paper on getting my Sony 49" 4K TV to do 1080p@120Hz without dropping a frame every 5 seconds over Display Port to active HDMI converter. Not a cable issue and it was hardly noticeable most of the time while gaming, but I could tell sometimes, so wrote a B/W gating app to study it. I was eventually able to figure out that I had to bias high to about 120.3Hz to negate the issue. Nvidia 1060, BTW.

I wouldn't be surprised if there is a 'restricted distribution' paper written for Sony internal use which documents the entire setup process... you wouldn't want just anyone to be able to pay TV prices to obtain the equivalent of a giant high Hz gaming monitor.

The time I spent on that issue cut into my Doom play time (using Vulkan API), the reason I bought the TV. Oddly, I spent way more time playing it on 4K@60Hz, just because, well, 4K is sweeter than 1080p at that screen size.
Awesome! The definition of a true enthusiast right there: not just noticing a problem, but digging down to the heart of the matter and figuring out WTF is happening. I don't want to trash talk Sony, but as a consumer electronics company I swear it intentionally handicaps its products at times. "Oh, you want feature X, which actually works fine on our mainstream product? Sorry, we disabled it and you need to by twice as much to get our high-end offering!" (And I fully realize Sony isn't alone in this behavior -- hello Intel Hyper-Threading!)
 
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A paragraph on copy protection built into each technology would have been nice.
Sure, I can add that. The short summary: both support HDCP these days, and that's pretty much required from the content owners who want to try and lock things down. But I'm pretty sure the protection measures have all been bypassed now. (Maybe HDCP 2.2 is still secure? Or, doing a quick search, it appears to be a bit more difficult to crack. I'm pretty sure HDCP annoys the end users far more than it inhibits pirates from doing their thing.)
 
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bit_user

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This is really ho-hum. I only moved from VGA to HDMI when the new desktop had a GPU that allowed it.
Aside from that ... no difference. I had no flickering or noise with VGA. It worked perfectly. The HDMI is no better.
Once again ... ho-hum.
??? The article barely mentioned VGA! DisplayPort is something entirely different, as the article quite thoroughly explains.

The biggest issue with VGA is that it limits resolutions & refresh rates (although I've used it for 1920x1200 @ 75 Hz). Here are some other technical disadvantages of VGA:
  • As you push the resolution and refresh rates, the image can start to look a bit soft.
  • If the cable isn't the best quality or the connection is poor, you can get ringing or ghosting. Also, the black level can sometimes wander.
  • The monitor needs to be adjusted so it aligns with the active picture area of the signal. Some monitors can do this automatically, and some implementations of that work better than others.
  • The monitor doesn't necessarily know the aspect ratio of the signal. So, if you pick a 4:3 resolution, to be shown on a 16:9 monitor, you're likely to see a squashed/stretched image, instead of the vertical black bars that one would expect.
Interestingly, the predecessor to VGA was EGA, which was digital (but only 16 colors). So, it's a little weird to consider that analog VGA was a step forward from that. Anyway, the transition from analog (back) to digital is anything but "ho-hum"!
 

bit_user

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I don't want to trash talk Sony
I do.

For a long time, I noticed they were really trading on their name. I called it the "Sony tax", since their stuff was always more expensive for no obvious reason or benefit. So, I never bought their consumer electronics (except PlayStation and PS3).

Initially, my favorite consumer electronics brand was Panasonic. Then, I sort of switched to Samsung, and now it's LG.
 
Only if you want HDR. Otherwise, you can still get full RGB 8-bit @ 120 Hz, with DP 1.3 (HBR3):

Yeah, it's supposed to allow for 120 Hz, and it does seem to allow it now. I swear last time I checked Nvidia's drivers automatically dropped the color depth to 4:2:2. It might have been with a different GPU, though, like a GTX 1080 Ti or something. 4K 120 Hz at 24 bpp is super close to the bandwidth limit of DP 1.4, so I wonder if sometimes (on certain cards?) it goes over the limit and downgrades.
 

JonDol

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Nice article ! I instinctively went with DP whenever was possible (also thanks to Dell for being among the first adopters of DP on their laptops) since I felt that with higher bandwidth one could do more or the hardware will struggle less to do the same as with HDMI, without knowing the technical details as you clearly explain. You mentioned cable quality a couple of times and this is important and unfortunately most consumers ignore this and buy the cheapest available cables then they wonder why the image quality is lacking. Is there any practical way for consumers to compare or benchmark the capabilities of their cables ?
 
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Nice article ! I instinctively went with DP whenever was possible (also thanks to Dell for being among the first adopters of DP on their laptops) since I felt that with higher bandwidth one could do more or the hardware will struggle less to do the same as with HDMI, without knowing the technical details as you clearly explain. You mentioned cable quality a couple of times and this is important and unfortunately most consumers ignore this and buy the cheapest available cables then they wonder why the image quality is lacking. Is there any practical way for consumers to compare or benchmark the capabilities of their cables ?
Because HDMI and DisplayPort are digital signals, cable quality has zero impact on the actual image quality. Either the signal gets to the destination and the cable works, or it doesn't. Degraded signals usually cause a full loss of image, sometimes periodically and sometimes they just never work. At least in my experience, I've never seen a digital signal 'look better' with one cable vs. another.

The biggest problem with lower quality cables is that they often can't handle higher bandwidths, or they have to be shorter. For example, I bought a (cheap) 3m DisplayPort cable at one point. It could do 1080p and 1440p at 60 Hz just fine. 4K at 60 Hz caused a flicker -- meaning, the display would black out and come back on every few seconds. 1080p and 1440p 144 Hz either did the same thing, or simply failed entirely and the graphics card drivers apparently detected this and removed the option after I tried it.

The same goes for any adapter, like mini-DP to full-size DP. They can cause a loss of signal integrity, which can then cause periodic display blanking.

Generally speaking, my experience is that HDMI and DP cables either work for the resolution you want to use, or they fail. Most 2m cables will do just fine up to a certain point, beyond which you need a higher quality cable. DP8K certified cables should work for just about any signal, and certified Ultra High Speed HDMI cables should also be good. If you want to step down on HDMI, you can also get a certified Premium High Speed HDMI cable and it should do up to 4K 60 Hz at least, possibly more.

Something else to note is that if you want to use a longer cable -- 3m DisplayPort or 5m HDMI, for example -- you'll definitely want to get a certified cable. The certification 'proves' that the cable has been tested for compliance. Non-certified long cables are very likely to fail at higher resolutions and/or refresh rates.
 
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