Of course it will display more. Your operating system allows you to scale your everything up/down. Scale them to the size that is comfortable on your 27". Scale them to the same size on your 55". You can display twice as much and it works in portrait mode (of course it is up to you to figure out how to mount it). Anyway, I just scale everything until I like the size of the text. Take care.
Here's an example of a chart on UHD monitor with text scaled up. I could scale up the text in the title bar also if desired. The primary benefit to using 3x, UHD monitors vs. a TV a monitor is to be able to display more bars at one time.... ~70% more in this setup. And the 3x UHD setup is smaller (~49", diagonal) than a 50" TV.
You're also looking for a desktop computer. If you want to save some money buying used, my rec is the Dell T5810 workstation (I have 4 of them). You can find many on eBay with just about any configuration you want... and can get a Square Trade warranty if desired. No need to spend more than ~$400 on a quality machine that may have cost up to $3,500 new, depending upon how equipped (no kidding, $3,500!). My primary rig, excluding monitors, was $350.... including a quality quad port video card. A couple of months ago I alerted the board about a vendor selling like 50, T5810s... significantly better equipped than mine.... for $320. They didn't last long at that price. FWIW...
No need to be in a hurry. Know what equipment you want/need and you can watch for a bargain. But when you see one, you'd better jump on it. I've tried to buy a great bargain perhaps a half-dozen times over the years only to find somebody beat me to it. Others are bargain hunting for a good price on things, too.
For the past 12 years I was using 3 x 24" HD screen. I just replaced one of my 24" with a 43" 4K. Very good decision.
I give up. Somebody else take this. I have used multi-monitor setups at work and large TV monitors at home. Large TV all the way for me. Anyway, Have a good day
If I were buying a computer for trading, I would get something like this https://www.newegg.com/p/1VK-001E-413T5 Throw out the 8 gigs. Buy 16 gigs of faster 3200 memory for under $100. Buy a large hard drive +/- $100. $760 + $243 for the 4K TV. These are cheap computers, and at this point, you will have exhausted the expansion capability. In fact, this is what I have done for years. All computers around $700 - $800. First i7-2600, several years later an i7-6700. A few years ago I built a Ryzen 7 (it cost more) for development. All still in use. I figure that every 4 or 5 years I will want a new computer anyway, so if I were to buy the above computer, I would probably retire the i7-2600 or just keep it for Linux. Take care.
No sir, you are wrong. A 4K TV is only 3840x2160.... regardless of whether it's 50" or 85". 3x, 27" UHD monitors are 6480x3840 in portrait mode.... and a bit smaller than a 50" TV.