We bask in 5K glory with the Dell UltraSharp 27 UP2715K
Look at these adorable kittens! We walk you through the ins and outs of 5K and tell you what you'll need to run it.
By Gordon Mah Ung
PCWorldSep 15, 2015 3:00 am PDT
Who doesn’t want more pixels? If you raised your hand, go to the back of the classroom and sulk with your beige 800×600 CRT, because as controversial as it is to promote more pixels, one look at Dell’s beautiful UltraHD 5K monitor will have even the haters convinced moar is better.
That doesn’t mean 5K is without its warts—which I’ll walk you through—but good gods, seeing 5120×2880 pixels spread across the UltraSharp 27 UP2715K is enough to make a grown nerd cry.
To give you an idea of just how many pixels a 5K monitor packs, you can’t just look at the raw resolution. You really need to think about it in megapixels.
A typical 23-inch, 1920×1080 monitor is about 2 million pixels. A 27-inch 2560×1440 notches that up to 3.7 megapixels. The current 4K buzzword, with its resolution of 3840×2160, takes it to a juicy 8.2 megapixels.
But that Dell? That UltraHD 5K monitor? Think 14.7 million pixels, or more than seven times the pixels in your Full HD monitor and about 70 percent more than an UltraHD 4K monitor. Dayum.
Do you really need more pixels?
The pursuit of pixels is indeed controversial. On one side you have the people who believe once you’ve exceeded a certain pixel density your eyes can’t see more, so it’s overkill. On laptops, more pixels means a battery life penalty. Even worse, all those pixels mean you need a big, hairy GPU or GPUs to push it in gaming.
On the other side, you have those who think pixel density is the bee’s knees. It smooths out everything so you’ll never even remember what a pixel is. More pixels can also have a practical impact in giving you more desktop real estate to work with. Anyone who works with CAD or any other discipline that requires an enormous amount of data on the screen knows the value of more pixels.
Here’s a quick way to illustrate it using cats. I’m allergic to cats and don’t have cute cat pics of my own, so thanks to Josh Norem of the Furrtographer.com for use of his supercute images.
Here’s what a 1920×1080 image or FHD would look like at 100 percent on the 5K monitor. Next is the popular 2560×1440 resolution that’s usually found on 27-inch monitors.
Now let’s finally jump it up to full 5120×2880 resolution. Yes, bask in the cute kitten.
The first 5K monitor
Dell’s UP2715K was officially the world’s first UltraHD 5K monitor. It’s designed primarily for the professional markets and originally had a price tag of $2,500. Of course, everyone knows Apple soon rained on that parade with its 27-inch 5K iMac for $2,200. HP actually mocked both with its own 5K Z27Q monitor for $1,300. Dell has since had to adjust the UP2715K to about $1,700 on the street.
The Dell monitor measures about 27 inches diagonal, has true 10-bit color support, and a color gamut of 100 percent of the sRGB and 99 percent of the Adobe RGB gamut. The rated contrast ratio is 1000:1, and the viewing angles are the typical 178 degrees horizontal and vertical. And yes, of course, it’s an IPS panel, which also means it has a response time for gray-to-gray of 8ms. Though beyond the scope of this story, I’ll say I compared an identical image shot on a 50-megapixel EOS 5D on the 27-inch 5K iMac to the Dell, and the Dell had a very slight edge in highlights. Both were stunning, and there’s evidence to suggest that both use the same LG panel inside.
The differences may be down to how Apple and Dell tweak the internals and calibrate them from the factory. Just so you know, I displayed the image on the Dell using the iMac 27-inch to power it, to reduce variables in the comparison. The Dell does have slightly less glare. Side by side, though, both are stunning—and well, 10K of resolution! (not really but 5+5=10 right?).
For ports, you get five USB 3.0 plus two DisplayPort 1.2 and one mini DisplayPort. That gets us into the tricky parts of 5K monitors.
DisplayPort 1.2 has just enough bandwidth to run a 4K monitor at 60Hz, and 5K pushes it over the edge. To get 5K to work, you’ll have to use two DisplayPort 1.2s simultaneously. Fortunately Dell includes the two DisplayPort cables you need. They’re actually connected and color-coded to help you plug them in right. You’ll need to plug them in the right order on both the monitor and your GPU.
The good news is, 5K seems a little more mature than 4K was when it was first introduced on the PC. Many early 4K monitors required switching between single-stream transport (SST) or multi-stream transport (MST) mode, and they were flakier than a box of breakfast cereal. Early units I used in 2013 required having a second monitor for those times when the machine would POST (power-on, self-test) but you’d get no image on the 4K monitor.
No issues, but…
The Dell gave me no issues like that. I tested it with an Origin PC Millennium with three GeForce GTX 980 Ti cards in Tri-SLI, and an Alienware X51 R3 with a GeForce GTX 960 with no issues. It simply booted, and within a few moments I was at the desktop. I also tried the Dell 5K panel plugged into a 5K iMac with no issues.
One thing I’m going to point out right here, though, is you might need a second monitor handy for going into the BIOS. When in 5K mode and plugged in using the two DisplayPort cables, there’s no way to get into a system’s BIOS or UEFI settings. Dell says when this happens, break out another monitor.
I found an easier solution. though no less irritating: If you need access to your BIOS, break out a mini-DisplayPort cable and plug it into the monitor and then unplug your two full-size DisplayPort cables and plug the mDP cable into your system. Voila, you can now go into your BIOS. At least I could on the Asus board I tried it on. That mDP port, btw, maxes out at 4K.
This isn’t a great solution. You have to unhook your cables, crawl to the back of your PC and make changes, but it’s better than having a second monitor sitting on your desk just to use the BIOS.
There have been other issues since 5K was introduced, but most of them (according to this page at Dell) seem to have been fixed by drivers. After reading this Dell page, I had nightmares of my early 4K experiences, but it did go off without a hitch on no less than three systems when I used it.
What does it take to run?
Obviously, you’ll need a PC with dual DisplayPort 1.2 ports handy and a GPU that supports it. Dell’s short list includes: “NVidia Quadro series, K2200, K4200, K5200. GeForce series, GTX980, 970, 960. AMD FirePro series eg: W9100, W7100, etc. Radeon series eg: R9 295X2, HD7990, etc.”
Mac users who want to run this panel will need a Mac Pro cylinder, an iMac 27-inch 5K, or a MacBook Pro 15 with a GeForce GT750M GPU aboard and OS X Yosemite or later.
Of course, that’s just for 2D work. What does it take to game at the Dell’s native 5K resolution? I’d recommend no fewer than two GeForce GTX 980 Ti cards, and you probably should think about three cards.
For example, I ran Tomb Raider set to Ultimate on an Origin PC Millennium with three GeForce GTX 980 Ti cards in it. The result you can see for yourself:
Going from a single GeForce GTX 980 Ti to three GeForce GTX 980 Ti cards pays handsome dividends. And this is just Tomb Raider. Anything more graphically intense, well, you better think about having at least three GPUs.
Dell’s UltraSharp UP2715K is stunningly beautiful and stunningly expensive to run. Besides the cost of buying the monitor, there’s also the cost of driving it with enough GPUs to game at its native resolution. For a lot of people, probably most people, it’s just not worth it. You could, for example, get three 27-inch monitors at 2560×1440 side-by-side for less than the Dell.
But that doesn’t solve the problem the 5K Dell solves—maximum pixels on a single panel. Three 27-inch 2560×1440 pixels still adds up to about 11 million pixels spread across three panels—that’s still almost five million pixels fewer than the single Dell 5K monitor.
For someone who truly needs that many pixels on a monitor for CAD/CAM work or other professional chores, it’s worth it. And of course there’s the one thing everyone needs a monitor for: cat pictures.