My new Mac Pro is running my two 1560 x 1440 monitors at 1008 x 1334. The only choice is 1024 x 1280. Why?
Mac Pro (Late 2013), OS X Mavericks (10.9.2), The monitors are DELL U2713HMs
What port are you using on the Dell Monitors?
What adapter(s) are you using to get there?
The Dell U2713HMs have DVI output and the Mac Pro has only Thunderbolt ports so I am using Apple DVI to Mini Display port adaptors because Apple doesn't supply a true thunderbolt adaptor , although MIni Display Port fits in a Thunderbolt socket.
I have since found out that the adaptor is the problem and it is not capable of handling YCbCR and the answer is to load a script that forces the graphics card to down grade the out put to RGB. I haven't done it yet because it doesn't sound like a very elegant solution.
Thanks for your interest.
I am wondering if it would work better to use the HDMI ports on the monitors via HDMI to Thunderbolt adaptors, assuming that Apple makes a real HDMI to Thunderbolt adaptor, ie not just Mini Display port which might be one of those transitional products that Apple has in effect abandoned, like Fire Wire. I can borrow one tonight so I will try it and see.
According to information on a dell web site, these are the ports available:
Connectivity
• 1 Dual Link Digital Visual Interface connectors (DVI-D) with HDCP
• 1 DisplayPort 1.2 (DP)
• 1 High Definition Multimedia Interface (HDMI)
• 1 Video Graphics Array (VGA)
• 1 USB 3.0 upstream port
• 4 USB 3.0 downstream ports
• 1 Audio out
• DC power connector for Dell Soundbar (AX510)
.
Consider using a Mini DisplayPort to DisplayPort cable, no adapters, for under US$10.
There is also an HDMI port on the Mac Pro (late 2013) that could be used directly with an HDMI -- HDMI cable.
I am not certain this would solve the "false colors" problem, which I HAVE seen reported here and have seen fixed easily, perhaps by the script you mentioned.
Thank you, I had mistaken the Display Port for a second HDMI.
I was having issues getting two 30" Dell monitors to run at 2560x1600 with the nMP. One would and the other wouldn't. I finally fixed it running one through HDMI.
I used SwitchResX from http://www.madrau.com. That preference panel makes display configurations possible that aren't normally available.
This morning I experimented with 3 alternative connections, HDMI to HDMI on the Mac Pro, HDMI to Mini Display Port cable, and HDMI to Apple HDMI adaptor to Mini Display Port. The result was the same each time, the display down grades to 1080.
Then I downloaded Switch Res X and tried it. Same result, even when I enter a custom setting the display defaults to 1080. The custom menu in Switch Res X shows the custom setting correctly but displays it as "Status - Not activated- invalid?" I also tried to down rate the Frequency to 59 MHz because the FAQ says the setting must be different to the Apple setting or it wont run. Same result.
The FAQ at SwitchRes X seems to be indicating that the purpose of it is to help show lower res TV on a high res monitor, so I was surprised by the reply above by Wayne of America, the resolution you achieved is 2560 x 1600, ie higher than the Apple Thunderbolt display, maybe there is something significant about that. Is there some way to force the setting in SwitchResX?
At this stage there is also still the chance of using a Display Port to MiniDisplay Port cable, as recommended above by Grant Bennet-Alder. I held off trying this because I didn't want to add to the drawer full of Apple adaptors in my desk.
Hi Noel, I found SwitchResX a little frustrating to activate the desired setting. It seems that after a desired setting is chosen you've got to "Save" (that wasn't clear to me). The you've got to re-boot the Mac. This is using the HDMI port on the nMP to the DVI port on the Dell 30" monitor through a regular HDMI to DVI cable..
I messed up a couple of times till I figured it out, but then I'm a "baby-boomer".
Thank you, I made the same error of not looking in the old fashioned menu bar at the top, but it did not change anything, however I can't duplicate your HDMI to DVI cable at the moment, I am using HDMI to HDMI on one monitor and HDMI to MiniDisplayPort on the other. I will have to look in my stash/junk room at home.
In the mean time I have taken the advice of Grant Bennet-Alder higher up the thread. I searched for a MiniDisplayPort to DisplayPort cable and found it at Macfixit Australia. In the reviews it says it fixes the Dell monitor to Mac problem.
If only there was a human behind a desk at Apple or Dell they just might have noted this connection solution and put it on their sites, or even included the appropriate cable with the product!
Congratulations to Grant Bennet-Alder, the correct answer is use a DisplayPort to MiniDisplayPort cable.
As usual, great advice from Grant. We've used this $100 adapter from Apple a number of times, though the feedback/reviews on Apple's Store page are "less than stellar". When they work they're great but my experience (and others) has been that you may need to exchange your purchase a number of times till you get one that works. It may be just that I'm using non-Apple monitors.
It may be just that I'm using non-Apple monitors.
If there is an issue, I would say it is more likely to be the failure of the (substantial amount of) electronics in those adapters.
If I had to speculate, i would guess that they are not properly protected from electric shocks induced on their cables.
Mac Pro downgrades 2560 x 1440
