240hz? Blackmagic eGPU + 2015 MBPr

[gigadad_exe]

I'm currently running a Blackmagic eGPU with Radeon RX580 with my 2015 MBPr 15" (w/Purge Wrangler patch to work with TB2). I've started gaming with GeForce Now, and am thinking I need to upgrade refresh rate (I'm using two 27" Thunderbolt Displays).

240hz gaming monitors are easy to find, but will I actually get 240hz from my hardware? Will I also be able to run my Thunderbolt Displays alongside it with them running at their max 60hz?

Thank you for any insights and guidance.

 

[AlexMaximus]

From the PC world of view, I'd say chances are hight that it will NOT work with your current setup.
Those Thunderbolt Displays are most likely not suited to run at 240hz. I have the older Cinema Displays with
Mini Display Port. They are great for my needs, but you can't push them much further. Even if you can find some way to force setting in Widows on those, it's highly likely the displays will just shut down or quit working. I would not try it. Go and get a real gaming setup, this route will end in a dead end.

 

[gigadad_exe]

ah, I should clarify: I want to BUY a new 240hz monitor to run alongside my dual Apple 60hz monitors. I have previously run three 27" 60hz monitors without issue. I feel like the eGPU should be able to run at least 120hz, but as I am not the most technically savvy person, I want to confirm that I can have two monitors running at 60hz while the third runs at 240 (or 120).

I am weighing buying a separate 4080/4090 based gaming PC, but for me using Windows is like eating pork to Jews and Muslims - it wouldn't kill me, most people do, and I'll do it if I have to, but I won't like it. Cloud gaming works very well with relatively few drawbacks.

 

[AlexMaximus]

ah, I should clarify: I want to BUY a new 240hz monitor to run alongside my dual Apple 60hz monitors. I have previously run three 27" 60hz monitors without issue. I feel like the eGPU should be able to run at least 120hz, but as I am not the most technically savvy person, I want to confirm that I can have two monitors running at 60hz while the third runs at 240 (or 120).

I am weighing buying a separate 4080/4090 based gaming PC, but for me using Windows is like eating pork to Jews and Muslims - it wouldn't kill me, most people do, and I'll do it if I have to, but I won't like it. Cloud gaming works very well with relatively few drawbacks.

Ok, that scenario is a different story. The 240hz capability is a display function and tied to the hardware of that screen. I am not sure how many display ports you have on the Blackmagic eGPU. Three displays might be bit too much for that 580. However, what might work is to just unplug those Thunderbolt displays and connect the new 240hz as single screen while you play that occasional game. Since you have a laptop, I would just visit a Electronic store and ask that staff to connect it for a short test run on one of their 240hz demo screens, before you buy one. Black Friday and Cyber Monday is coming up anyways, so you have good opportunity to get one for cheap and tie that visit/test run with that purchase together. Then you have absolute certainty.
What you may have to keep in mind is the fact that your 580 has no regular display port, yours has HDMI only I believe. There are many different HDMI standards that you need to check first. Most likely your new 240hz screen has the newest HDMI 1.4, but your HDMI port on the eGPU may have an older standard (1.2 or older) with some kind of
limitations. That means also your HDMI cable needs to be checked if its VESA compatible. This means also you may want to check on site with different HDMI cables other than your own to see which combo pans out for you.

 

[arw]

I do not own said eGPU so no definite answer from my side.
For video, besides one Thunderbolt 3 port to connect the eGPU to your Mac, it features a second 40Gb/s Thunderbolt 3 port and one HDMI 2.0 port.
The TB3 port is connected to a Titan Ridge Thunderbolt 3 controller (Intel JHL7540) for possible daisy-chaining.
Blackmagic only mentions up to 6K compatibility (for the Pro Display XDR).

Out of curiosity, how did you connect your three displays in the past? Via a TB3 dock or did you connect one display directly to the MacBook?

Did you check how much the GPU is currently utilized when gaming?
Depending on the game/resolution, you might not get even close to 240 fps even if the eGPU could output 240 Hz.

(Btw. PureWrangler has been superseded by Kryptonite/OpenCore which also isn't actively maintained anymore.)