MP 1,1-5,1 Larger monitor choices for AMD Radeon R9 280x

[gtackett]

On my cMP 5,1 running Catalina with OpenCore (Martin Lo's distribution) I'm currently using a flashed AMD Radeon R9 280x with a Dell U2412M monitor.

System Information shows the following details for them:

AMD Radeon R9 280x:
Chipset Model: AMD Radeon R9 280x
Type: GPU
Bus: PCIe
Slot: Slot-1
PCIe Lane Width: x16
VRAM (Total): 3 GB
Vendor: AMD (0x1002)
Device ID: 0x6798
Revision ID: 0x0000
ROM Revision: 113-E2080C-101
VBIOS Version: 113-5E249000-O42
EFI Driver Version: 01.00.624
Metal: Supported
Displays:
DELL U2412M:
Resolution: 1920 x 1200 (WUXGA - Widescreen Ultra eXtended Graphics Array)
UI Looks like: 1920 x 1200
Framebuffer Depth: 30-Bit Color (ARGB2101010)
Display Serial Number: YMYH139F0G0S
Main Display: Yes
Mirror: Off
Online: Yes
Rotation: Supported
Automatically Adjust Brightness: No
Connection Type: Thunderbolt/DisplayPort

I'd like to move up to at least a 27" monitor, but before shopping I'd like to have some idea what the R9 280x can support as far as resolution and refresh rates.

As for pixels, though I'm rather nearsighted I find the pixel pitch I'm getting (I calculate about 94 ppi) is comfortable for me. I might be okay with a slightly higher value, I suppose.

Current monitor connections:

• DisplayPort: Radeon DisplayPort
• DVI-D: Occasionally other computers but not the Mac Radeon card.
• VGA: Occasionally used but could use an adapter.

I was told by the person who flashed it that the firmware on the Radeon board doesn't support one of the connectors I don't use, either:

• One of the two DVI connectors, or,
• The HDMI connector,

But I don't recall which.

Things that aren't concerns of mine:

• Gaming
• 4K
• USB ports on monitor

Optionally would like to have:

• Built-in speakers, though I'd be content to continue using my clunky, ancient Altec Lansing desktop speakers since they still sound okay.
• Adjustable height and horizontal+vertical screen angle (or else VESA compatibility).

I will likely shop either currently available models, or refurbished no longer current models, and would like to keep price under $250.

So what I hope some responders can offer are:

• Resolutions and refresh rates supported by AMD Radeon R9 280x
• Suggestions as to specific monitors
• Tips, etc.

 

[h9826790]

If you don’t need 4k, then don’t go 4k. It will just make the situation more complicated with a Flashed 280X.

For 27”, most people prefer 1440P monitor (same as the 27” Apple Cinema Display).

But if your viewing distance is a bit far (e.g. 80cm), then most likely keep it at 1080P will be easier to read the text.

 

[gtackett]

If you don’t need 4k, then don’t go 4k. It will just make the situation more complicated with a Flashed 280X.

For 27”, most people prefer 1440P monitor (same as the 27” Apple Cinema Display).

But if your viewing distance is a bit far (e.g. 80cm), then most likely keep it at 1080P will be easier to read the text.

I suppose monitors capable of 4K, as increasingly many are, will also run at lower effective resolution. How does that affect pixel pitch?

 

[h9826790]

I suppose monitors capable of 4K, as increasingly many are, will also run at lower effective resolution. How does that affect pixel pitch?

It's not about the supported resolutions, but for a 4K monitor to work at 60Hz properly, you should set the monitor to accept Display Port 1.2 input.

However, the Mac EFI UGA on your flashed 280X has compatibility issue with DP 1.2.

Therefore, you will have to set the monitor to DP 1.1 if you want to use the boot screen (otherwise, the computer will hang at start). Which will makes a 4K screen to run at 30Hz (if the output is actually 3840x2160 regardless what the UI resolution is).

This is why I said it will just make the situation more complicated.

It can work, but you can't have a "one setup fit all" situation.

Either you give up the boot screen for normal daily use, and only use boot screen on the day you really need it (most of the 280X has dual ROM design, this is very easy to achieve indeed).

Or you keep changing the monitor's input between DP 1.1 and DP 1.2. Assuming the monitor has this setting. Then you can switch the monitor to DP 1.1 during boot. And then switch it back to DP 1.2 once you boot to desktop. In this case, you can enjoy both boot screen, and using 4K 60Hz inside OS.

Or you keep DP 1.1, and force the graphic card to output something at or below 1440P. Not just UI resolution, but the actual rendered resolution. For 1920x1080, it usually looks OK on a 4K screen due to perfect match of 4:1 ratio. But for 1440P, it may looks a bit burry. Therefore, if you are happy with 1920x1080 (44% less working area compare to 2560x1440), then this can be the solution. However, it become meaningless to have a 4K monitor, why not just buy a 1080P monitor at the very beginning?

 

[gtackett]

I picked up a couple of LG 27MK400H-B monitors, 1920 X 1080 with HDMI and D-Sub VGA connectors. I've connected its HDMI to the single HDMI 1.4a on my Sapphire R9 280X graphics card (flashed for Mac).

My existing Dell U2412M monitor was already connected to the graphics card's single DisplayPort 1.2 connector. If I disconnect it, what is the best way to connect the other LG monitor, since it doesn't have DisplayPort? The graphics card has one usable DVI-I port.

So I'm going to need either an adapter from either DVI-I or DisplayPort, to HDMI (I assume the VGA isn't the best choice.)

I know there are active and passive adapters, and (I think) bidirectional ones. With my equipment, does it matter which I choose?

 

[h9826790]

For 1920x1080, almost any DP to HDMI convertor can do the job. Active adaptor is particularly for 4K 60Hz output, you don't need that if the LG monitor is just Full HD 60Hz.

 

[gtackett]

I’m not entirely satisfied with the LG 27MK400H-B monitors I recently bought. Partly, I miss the additional screen space (in pixels, not inches) available on my 24” Dell 1920x1200 monitor. I thought the easier to read (I’m pretty nearsighted, have astigmatism, and am over 65) larger screen would offset the loss of pixel space, and while it is easier to read, the image quality is poorer on the 27” 1080p LG and not just because the pixels are larger: the color space seems much smaller and less vivid.

(And the Dell stand is much more adjustable.)

So I’m wondering what I should consider instead of the LG monitors, and wondering if there might be some monitor larger than 24” and resolution intermediate between 1080p and 1440p (1200, perhaps, like my 24” Dell??) and to use two such with my AMD Radeon 280x flashed with Mac EFI UGA.

 

[h9826790]

I’m not entirely satisfied with the LG 27MK400H-B monitors I recently bought. Partly, I miss the additional screen space (in pixels, not inches) available on my 24” Dell 1920x1200 monitor. I thought the easier to read (I’m pretty nearsighted, have astigmatism, and am over 65) larger screen would offset the loss of pixel space, and while it is easier to read, the image quality is poorer on the 27” 1080p LG and not just because the pixels are larger: the color space seems much smaller and less vivid.

(And the Dell stand is much more adjustable.)

So I’m wondering what I should consider instead of the LG monitors, and wondering if there might be some monitor larger than 24” and resolution intermediate between 1080p and 1440p (1200, perhaps, like my 24” Dell??) and to use two such with my AMD Radeon 280x flashed with Mac EFI UGA.

May be you can go for the ultra side monitor (e.g. 2560x1080).

I understand 1920x1080 only provide limited desktop space. However, unless you really need more vertical pixel. In general, go for higher horizontal resolution to increase desktop space is easier.

By moving the dock to the Left / Right, 1080P should provide roughly the same vertical space as 1200P with the dock at bottom.

I am now using a 3840x1080 monitor. It's very OK for normal daily use. I can easily open 3 windows and put them side by side. It works like three 4:3 monitors with no gap in between.

But if you don't need that wide, most likely 2560x1080 is a reasonable option for you. So you there are more desktop space for you to work with, but the text etc won't be too small.