Mac Pro not recognizing correct monitor?

Thank you for your suggestion. I'm going to give this a try. I don't mind using the LG monitor in an exaggerated stretched-look mode right now, but when it comes to my photography and 3D modeling it is going to get in the way. I'd hate to have to get rid of this monitor because of my ignorance before I bought it.

Hi Grant, I'm learning a lot about monitors in a crash course now!

There is so much conflicting information out there and it was due to that I thought the monitor would work out of the box. On the one hand, the link you cited notes which Macs can support 4K (and ultra widescreen is included in that class), but it says that MDP or HDMI should work. On the other hand, many people including you have stated that HDMI maxes out at 1080, hence my confusion. Other sites like CNET talk about using HDMI for 4K televisions and monitors too.

I was just curious, would purchasing the below-mentioned mini MDP to HDMI active converter or upgrading my admittedly old graphics card (NVIDIA GeForce GT 120 with 512Mb of RAM) to something more current with different ports and power make a difference?

I'd hate to give up on this otherwise great monitor; until recently, I thought that any monitor was like another with the exception of the screen aspect or DPI resolution. I had no idea there was so much more to take into account?!

Thanks!

Hello Mark,

Yes! I went through exactly the same thing as you. Since I do a lot of photogrammetry and light video editing I might just grab a graphics card from New Egg and replace the stock GT120. Partly it is to keep this monitor but also to gain some much-needed speed when doing my work. I'm also adding more RAM to give my Mac Pro more resources to play with.

I know I'm just throwing more money at this problem instead of getting at the precise cause of it, but like you, I could only conclude that there was some kind of drivers issue. I don't have access to other computers to test this monitor on, but I have heard of other owners of this monitor testing it for the same reason. Oddly enough, the people who seemed to be having problems with this LG monitor are also Mac users, all using older equipment too. Windows in older devices plays nice with it.

I am tentatively concluding that while the GT120 should be able to output the correct aspect ratio and resolution, for whatever reason it can't or won't. I figure a different graphics card couldn't hurt for helping with this and my work anyway.

There is support for far more graphics cards coded into the Mac OS from 10.9 onwards. This now includes many previously PC-only cards. The only limits that I'm aware of now is making sure I don't use a graphics card that is too power hungry and being aware that since PC graphics cards use BIOS instead of EFI, I'll lose the grey boot screen.

I'm mulling over various EVGA GeForce GTX cards, from the 750 Ti to the 950 and 960, probably with 2GB, maybe 4GB if the higher end card doesn't draw too much power. Those cards do support 4K natively and should all play nicely with our model of Mac Pro. I'm going to make up my mind and order one of them on Tuesday and hopefully have an update by the end of next week. I am a little constrained by my budget as I just broke my trusty Pentax yesterday and have started looking for a replacement.

I've gotten pretty spoiled with the great ultra widescreen aspect in this LG monitor and it would be ironic that I'd have to drop more coin on a standard 1920x1080 than what I spent for this.

Hello Mark,

I just ran across this intriguing code/driver work around patch on Github. It notes that an active display port to HDMI adapter is needed to make the patch work. https://github.com/Floris497/mac-pixel-clock-patch

I just placed an order at Amazon for an active mDP to HDMI adapter following the helpful link supplied by ILLASS above. Since I'm not an Amazon Prime member, it won't be in my mailbox until friday or monday at the earliest. Once I get that active adapter (right now I'm using a passive mDP to HDMI adapter) I'll try out that patch and let you know if it worked or not.

Warmest regards,

Jerry

Hello Mark,

I was busy last week before giving the open-source patch I suggested a try last night. It didn't work.

Since it involves disabling S.I.P. and using Terminal in Recovery Mode, I was a little apprehensive since I'm known to transpose the odd letter here and there as I type. Just to be safe, I relied on copy and paste. While it appeared to have worked when I looked at the Terminal messages after invoking the patch, the messages weren't precisely the same as what the page said it should read. I should've taken screenshots to share, but I don't think it quite worked in my case.

There might be a little more work involved as I noticed that there were more things to tweak deep in the system if I didn't get a certain confirmation message. Since it was late last night, I was tired and close to giving up.

After turning S.I.P. back on, I tried using an active mDP to HDMI adapter and checked the monitor preferences. Even with pressing the Option key while looking for extra resolutions, nothing had changed. As a last thought, I tried switching from 60Hz to 30Hz to see if that would finally output a proper full resolution for the LG. I got the dreaded "Out of Range" error message on the screen and I couldn't escape and default back to the previous monitor resolution. At that point I finally threw in the towel as I was too tired to try anymore.

A friend who was visiting while I attempted to invoke the patch let me borrow a different monitor. The monitor is a 27" Samsung LED, with the standard 1080X1920 display. It was instantly plug and play even as I used the HDMI cord. The only thing I had to do is check the Overscan box.

Here is a side note that I thought was worth bringing up: I'm still using the original GT 120 graphics card. I had added two 16Gb sticks of RAM plus a SSD to my Mac Pro and made it the default boot drive. I've sym-linked my home folder to a Western Digital black 1TB to keep the SSD from getting clogged up. After all that, I hadn't noticed much of a change in the performance of my Mac Pro aside from a much faster boot up.

After replacing the LG with the Samsung, suddenly my Mac Pro is far faster in every way. My Magic Mouse, which would sometimes stutter and not track quite so accurately at times now tracks smoothly and perfectly. My projects in FCP X and Photoscan Pro are faster than before too. It is as though I have a brand new Mac.

I can only conclude that the current GT 120, while adequate for almost everything else, slows to a crawl when I try to use the LG monitor with it. The only solution I can see to keep it and use it is to replace the graphics card. At least Apple has been coding support for non-EFI graphics cards into the OS since 10.9 as I won't be forced to fork over a small fortune for a Mac-specific card. The only thing I'll lose is the grey boot screen but for that same reason I'll hang on to my GT 120 just in case the need should arise.

Just in case you might be interested, here is a link to a list of 4K supported NVIDIA GeForce graphics cards:

http://www.geforce.com/hardware/technology/4k/supported-gpus

Not all of them will be supported by our particular Mac Pros as there are power supply limitations to consider, but there is a wide variety for almost every budget out there that should breathe new life into our beloved Macs.

Good luck Mark!

Sincerely,
Jerry

Well, I have some mixed good news regarding the LG monitor.

I purchased a GTX 960 with 4gb graphics card and installed the beast inside my 2009 Mac Pro after downloading, installing and turning on the Nvidia and CUDA web drivers. I removed the original GT 120 graphics card, installed the new graphics card and booted up.

Initially, I was running into problems with my LG complaining that the signal was out of range. Once I plugged in a TV next to it and pressed option in the display pane of the System Preferences, the LG popped up in all it's full resolution glory. The only stumbling block I had was that I needed to keep my TV plugged in while using the LG -- otherwise it would default back to the error message.

I slept on it and began trying to research it today and I was having no luck. On a complete whim, I took the HDMI cable from the TV and plugged it into the second HDMI port on the rear of the LG and suddenly it came to life without the need for the TV. Now I understand and feel stupid that I didn't figure it out sooner.

The LG is designed to be a split monitor, hence the two ports in the back. If anyone has experienced the maddening problem of window boxing or signal error, they need to plug in both ports in the rear of the LG monitor to make it work correctly. It all depends on your particular Mac and what sort of ports it has.

I'm thrilled to finally be able to take full advantage of the wonderful ultra widescreen LG.