"I can send an IP packet to Europe faster than I can send a pixel to the screen. How f’d up is that?" - John Carmack

I had a hard time believing that quote at the time. John ended up answering the question I asked about it on SuperUser [1] with details about his setup. His writeup is impressive: he actually set up a high-speed camera to record the actual latency.

[1] https://superuser.com/q/419070/2269

I used to work for Philips' TV branch, they used a similar setup. Instead of a camera they mounted a light sensor to the display and measured end-to-end delay for various color transitions (white-to-black, black-to-white, ...). All other manufacturers and many serious reviewers perform similar tests.

Of course, these tests are always performed with all built-in image processing disabled, those can easily add 2 frames of delay on modern televisions. MPEG deblocking and noise removal are performed by most TV brands to improve image quality at a cost of latency.

Right, the issue is that 60Hz is ridiculously slow. Ethernet hardware is multiple orders of magnitude faster. It's just because of broadcast TV and CRT legacy. G-Sync / FreeSync allow up to 240Hz, which is ~4ms latency.

60Hz is 16.7ms between each picture. However, that only gives you a lower bound on the latency. The actual time from GPU sending picture, to picture being on screen, can be a lot more. See the John Carmack answer above.

No, the issue was that he was using a display with a crazy amount of buffering because they were doing so much filtering and doing it poorly.

It's not just monitors even keyboards can have 40+ms worth of delay and it all adds up.

I don't think that was what he was referring to

"I video record showing both the game controller and the screen with a 240 fps camera" https://superuser.com/q/419070/2269

So, it's total response times from key press on a game controller to screen that is important not individual components. Sure, 0.04 seconds on it's own is not a big deal, but when 5 or six things take 0.04 seconds you hit noticeable delays.

G-Sync and FreeSync have nothing to do with the available maximum refresh rate on any monitor. That is a property of the display interface.

Solution: send the pixel to the screen over IP!

(joking, but with a tiny serious element)

this reminds me of the argument that instead of going to USB C 3.1 as the grand unifying connector for all peripherals (including video), we should have instead migrated to Ethernet cables for everything.

Currently ethernet doesn't look cheap enough for video to me.

Even a simple 1920x1080 60Hz monitor needs 3 Gb/s, a 2560*1440 144Hz monitor 13 Gb/s, a 4k 60Hz 12 Gb/s.

DisplayPort 1.2 offers 17 Gb/s and DisplayPort 1.3 offers 26 Gb/s.

40 Gbps and 100 Gbps Ethernet standard was defined in 2010 [1]. Google "buy 100 Gbps Ethernet" and you will find it is real, although currently is geared primarily for datacenters.

[1] wikipedia.org/wiki/100_Gigabit_Ethernet

Actually not a bad idea. Ethernet speed is one gigabit per second.

And there are high throughput devices like LIDARs (eg Velodyne LiDAR known from Google/Waymo self-driving cars) that are connected via Ethernet rather than USB.

Having 1 GBit Ethernet LAN network since 2004, I would prefer the possibility to upgrade to 10Gbit home Ethernet in near future.

It's a terrible idea. USB-3 is faster than 1Gbit/s. and there's no way you can drive a 5K monitor with any current or near future Ethernet standard, the bandwidth demands are too punishing.

Ethernet isn't optimized around short-haul signals, like computer to screen over a few metres at most, it's for 100m+ runs in datacentres. The signals have to be a lot more durable.

> "USB-3 is faster than 1Gbit/s"

But Cat 6 Ethernet is 10 Gbit/s.

Still not as fast as USB-3+Thunderbolt which is already 40Gbit/s and intended to be pushed to at least 80Gbit/s to support 8K screens.

> there's no way you can drive a 5K monitor with any current or near future Ethernet standard, the bandwidth demands are too punishing.

Really? You need more than 100gbit for 5k monitor? Because there is an 40/100gbit ethernet phy standard right now (has been for a while, since 2011). And work is being done on up to 200gbit (due to be ratified in late 2018).

5120 * 2880 * 32bits * 60FPS is only 28.3 Gbit and both 40Gbit and 100Gbit are well established standards.

Granted 40GB cards are running 50$ and 100Gbit cards are running ~700$, but that's most from the low volumes involved.

Really though the larger issue is Ethernet connectors are not designed to be plugged in and removed regularly.

> "Ethernet connectors are not designed to be plugged in and removed regularly"

Well could easily use a smaller and easier plug while still being pin compatible with ethernet.

ethernet over multimode fiber, I want to be able to have accessories hundreds of meters away from my computer

Careful, multi-mode fiber is near its scaling limits. 10GBASE-SR and 25GBASE-SR exist, but that's about it. (By contrast, 40GBASE-LR and 100GBASE-LR work over single-mode fiber, and DWDM + coherent optics can push the medium much further.) Wouldn't want to be stuck at 25 gbps forever ;-)

Yeah, some of us can type pretty fast. And for mice, some of us take clicker games seriously.

Just make sure those cables are never bent beyond the minimum bend radius.

It's amazing how much you can bend fiber. Fiber is really hard to break just by bending it, assuming it is well insulated. You can have performance loss with bends and kinks though.

Just use bend-insensitive fiber. It's not like copper cables like being kinked, either.

in all seriousness, why not?

The little plastic bits always snap off. Ethernet is great for semipermanent wires but not very good for peripherals like portable hard drives that are constantly disconnected and reconnected.

That problem is largely solved if you use 8P8C connectors with a rubber boot protecting the latching tab.

https://info.pcboard.ca/wp-content/uploads/2017/04/RJ45-Conn...

You can't tell me that's better than the USB-C connector.

Even HDMI is better.

My MacBook Pro’s USB-C connectors glitch if you move them slightly. I like the data rate but I’m not happy with RAM-pack wobble in 2017.

Even with the protective guard the little plastic tabs inevitably break on me. I can't even say those have fared any better than the unprotected versions.

My main complaint is that the protective rubber often gets stiff as it ages, which can make it pretty dang hard to remove old cables (until you resort to pliers).

Yeah, live hinges (that is, plastic bits that intentionally bend, not rotate on pins) are always going to break eventually. They're just so easy to make that it's a trade off that doesn't fall in the consumer's favor.

Living hinges can have lifespan in the millions of cycles with the correct materials and design. I'm sure it's possible to make an Ethernet connector that doesn't break easily, but it would cost more, and people aren't willing to pay.

What’s that to do with displays which aren’t unplugged frequently?

I plug/unplug from my display several times daily, since the MBP connected to it travels with me. Granted, the end of the cable in the monitor typically doesn't move¹

¹well, one of them. The crap LG monitors we have constantly forget about the peripherals that are attached, and one easy way to fix this is to detach/reattach the peripheral. I suspect that the company is never going to RMA these devices, sadly.

USB-C is used for all sorts of devices many of which are unplugged frequently.

The obvious ones: Ethernet cables are big (imagine one on a phone), and aren't designed to be plugged and unplugged the massive number of times that USB cables are (spring contacts wear out, little clips break).

well maybe the actual plug could be modified into a small form, while still being pin-compatible with cat 5/5e/6.

USB cables have little to do with the question of sending pixels via IP

Outside HDMI and some DisplayPort cables, all display connectors click or screw in

And we’re talking about desktop OS and displays

I'm not even sure about sending it as IP, rather as raw Ethernet frames (or simply just using the cables).

Some people tried, most went out of business. Either chapter 11 or bought for assets and IP. OnLive was the biggest one.

people working on compositors should have that printed out and hung above their coffee machines.

Indeed. I would rather take an excellent monitor, keyboard and mouse over a faster machine without them. Sadly this means I am pretty much limited to desktops as finding a laptop with a colour accurate 120Hz+ display with excellent keyboard seems to be impossible unless I look at some gaming laptop monstrosity that weights 5KG and has a 1 hour battery life. If anyone reading this know of a good laptop for development please let me know!

I can't offer you 120Hz, but the ThinkPad P51 with 4K screen has excellent colour gamut and accuracy and the best laptop keyboard in the business (with the possible exception of the old-style ThinkPad keyboard currently available only in the limited-edition "ThinkPad 25"). Battery life is pretty good.

Downsides: relatively bulky, pricey, no touchscreen or stylus input. (Upside of that: matt rather than glossy screen, which I think is difficult to combine with a touchscreen.)

Razer Blades? Not sure about refresh rate, but they have amazing keyboards and displays from what I hear

A good (and easy to remember/no other affiliation) source for this data: https://displaylag.com/

Is that still a good monitor vs 4k Dell offerings? Reasonable price here in Brazil.

Yes. I'm going to buy a second one in a few days (waiting to see if there's any Black Friday deals).

At this point I've been using 1 for almost a year and it's been nothing but great. I want to get a second one and orient it vertically.

That's an affiliate link fwiw

It's true, but there's also a 4,000 word detailed blog post that describes how I came to pick that monitor along with giving you insights and tips on how to pick a different monitor if that one isn't for you.

Why do people care about affiliate links? Serious question.

It's good to know that the person posting the link has a financial stake in it. Depending on the context this can mean a lot - like a review or recommendation.

Except it's Amazon. I could understand that position if it was a Dell affiliate link. But Amazon sells so many brands of monitors, any of which could carry the same affiliate code, that I don't see how that matters.

Just like the FTC, I do not care about the existence of the affiliate link being on HN, but only the disclosure. It makes for a fair(er) market.

I pointed it out, and I don't really care exactly--I just think it's common courtesy for the person to disclose it.

He didn't, so I did for him.

It's a conflict of interest. People are more likely to share links that get them the most affiliate $$$.

Why not go with 5k 27" monitor?

http://www.dell.com/en-us/work/shop/cty/pdp/spd/dell-up2715k...

Sure, it's over $1k, but if you're making $10k/mo writing code on it, then you should be able to afford it.

> if you're making $10k/mo writing code on it

hah... if only the world was silicon valley.

I mean, even in SV after taxes is that really a common salary?

Marginal Utility. A $400 27" 4k Ultrasharp isn't 1/3rd as good as a 5k 27" Ultrasharp.

I have the same monitor and it's pretty good.

The only thing I don't quite like is the pixel size, it's a bit small for native scaling. I kind of wish i had gone for the 27". I went with two 25" because two 27" were a bit too big for me.

P2715Q user here. One of the best monitors currently available, excellent color reproduction, top of the line quality. The 4K resolution however is a major problem when you are using Windows 7. Some applications will not play correctly when you try to scale up and at the end you get a mess. Windows 10 is better, but not perfect.

Have the same monitor, it's my third Dell monitor since I bought my 2405fpw back in 2005. I've always gotten excellent performance from them and the 2405 lasted 12 years.

The 4k resolution and scaling can cause issues with some apps as you noted. This is especially true if you use multiple panels with heterogeneous resolutions, connect with displayport and occasionally turn one monitor off. This causes windows to move everything to the other display which is a mess. However after futzing with it for a few days post-purchase I had it all working well enough to deal with, even though I occasionally get slack in an over-maxed window on the smaller display. Btw this program is really useful for smoothing mouse movement between the larger and smaller displays in windows 10: https://github.com/mgth/LittleBigMouse

I looked at 4k monitors but ultimately decided against it because as soon as you start scaling then you lose the extra screen real estate.

At 4k 150% scaling you end up with the same screen space as 2560x1440.

I personally like the higher resolution that scaling provides, but if you don't mind low DPI you should check out the 42.5" 4k panel that Dell makes[0]. I have one in my home office, and while it's not great for design and photo editing, the sheer real-estate available is mind blowing.

[0] http://www.dell.com/en-us/work/shop/dell-43-ultra-hd-4k-mult...

I agree and I _almost_ didn't buy the 4k panel, but as I noted in my comment above my first Dell panel lasted 12 years, and that's a long time.

Ditto, have a pair of those. They are the nicest I've used in a long time. Haven't noticed the Windows issues, but then I only run a couple applications under win in a VM. No issues with Linux.

They've released the UP2718Q at a serious price difference. I'd like to see one in person, but a 3x price increase requires a lot of improvement over an already great monitor.

I have a LG 27UD68-P (and just ordered a second one) and have found it pretty good for programming. Here in Europe they come with a swivel stand. The only real disadvantage compared to the Dell is they don't have DisplayPort daisy-chaining, but they support HDMI 2.0 so you can use that for 4k60.

Do you have 20/20 vision?

With glasses (20/20) I can comfortably read text from up to 3 feet away from the 25" version at 1:1 scaling. Even tiny text like the HN text field box.

We're using them at work, I'm very pleased with them. And the bang/buck ratio is great.

How is the 2715H?

All modern (2014+) Dell IPS displays have excellent input lag

If you are looking for such monitors, look for gaming monitors with TN-panel, with 2ms or 4ms response time. Compared to office monitors or even TVs there is a big difference. (mind that TN-panel have pro and cons)

Much worse viewing angles is a pain.

I agree.

Which is why its hilarious whenever I ask around for recommendations, especially on Reddit, everyone tries to peg it as a non issue. As if your head never moves and you only have one monitor.

The problem is:

TN Panel:

Pro: Cheap, low latency

Con: Everything else

What happens if you have multiple monitors? i.e. a TN-panel for gaming and an IPS for graphic design?

This is pretty much my setup. Higher quality TN panels don't have that much of a dropoff from median quality IPS panels.