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macmesser

macrumors 6502a
Original poster
Aug 13, 2012
921
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Long Island, NY USA
Sonnet makes two USB cards that I'm interested in: Allegro USB 3.0 4-Port and a Pro version which features a separate controller for each port. I saw no mention of how many controllers the standard version has so it could be one or two. I have a USB 3 graphics 4K adapter which I want to set up with a 4K TV as monitor. My question concerns how USB cards will divide the controllers' data transfer max throughput. In the case of the pro card all 4 controllers are completely isolated from one another, which I think might be be ideal for my application. Each controller offers max USB 3 capability. In the case of the regular version I'm guessing that there are two controllers (I have a question in with Sonnet, the maker) and each of the four ports shares a controller with one other port. Am I correct in thinking that if two devices are on the same controller but one of them is idle (e.g. a synced iPhone, a drive which is not doing I/O or a card reader that has completed its transfer), that the active device will have max USB 3 transfer rate? (The relevant hardware can be viewed at OWC in case the USB graphics adapter piqued anyone's interest in cost effective real estate.)
 
A "real GPU" might be overkill for a TV that can only do 30 Hz. A GT120 can handle that. Not the best performance, perhaps, but no worse than that USB adapter I'm sure.
 
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A "real GPU" might be overkill for a TV that can only do 30 Hz. A GT120 can handle that. Not the best performance, perhaps, but no worse than that USB adapter I'm sure.

Even though I assume OP don't need any high performance GPU. However, 4K 30Hz doesn't mean low demand. It's just depends on how you use the TV. Many real GPU can't maintain 30FPS in 4K gaming.
 
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Even though I assume OP don't need any high performance GPU. However, 4K 30Hz doesn't mean low demand. It's just depends on how you use the TV. Many real GPU can't maintain 30FPS in 4K gaming.

Thanks for reply. I just want the real estate because I typically work with many windows and programs simultaneously. The graphics cards that came with my Mac Pro are fine for my most intensive applications. My "focus" monitor will be my 27 inch Auria or 30 inch dell. I can keep anything else I want open on the TV. I won't be gaming but working with RDBMS, spreadsheet and script/text editor.
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Why don't you just get a 4K capable GPU? The OS X DisplayLink drivers will run your screen in software rendering mode, passing all the work to your CPU. A real GPU will give a better overall experience and won't cost much more than those Sonnet cards.

I will eventually upgrade but for now I'm pinching pennies. A GPU would indeed be overkill and if I got one I'd make it a good one. For now my eight core Mac Pro will work well with the adapter.
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Why don't you just get a 4K capable GPU? The OS X DisplayLink drivers will run your screen in software rendering mode, passing all the work to your CPU. A real GPU will give a better overall experience and won't cost much more than those Sonnet cards.

Thanks, My 8-core Mac Pro with 16GB ram seldom is called upon to break a real sweat so it might work given my usage scenario. If not I'll look for the card.
 
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I'm using a DisplayLink setup on my HP notebook at work with 2 FullHD displays (which consume pretty much the same bandwidth as 4K@30Hz). Windows is able pass the workload to the GPU, so this setup is working good for me, but that USB3 solution is the only way to get more than 1 digital output from that notebook, so I didn't have any alternatives.
I tried using the same setup with a MBP, and the result was a lot more sluggish, but you might not recognize that on a 4K@30Hz screen anyway.

I think the USB bandwidth isn't critical in normal office use since the DisplayLink drivers will only send delta changes through the cable.

However, I wouldn't do that on a Mac with PCI slots. You don't need some TitanX-class GPU if you don't plan to game @ 4K, some cheap options like entry-Kepler (e.g. GTX 660ti and above) or GCN1.0 (HD 7870 and above) will support 1 or 2 4K@60Hz displays. They are not high end obviously, but still as good as (or even better) than some GPUs Apple sells in 2016 in their Macs, hooked up to high-res displays.
You should get those GPUs for less than $100 on eBay. If you choose wisely, you can even get a flashable card.

Which GPU are you using at the moment? A HD 5770/5870 is able to output 4K@30Hz through display port, so a simple DP to HDMI adapter might already do what you need.
 
Not only is buying a GPU probably the better option, I think it's probably cheaper too.
Thanks for reply. Thinking about it, you're right about it being better. A 4K capable card is expensive but it could drive the 4K TV maybe better plus the existing monitor and would leave me with same amount of slots plus extra graphics card to sell. However, the 4K TV will be running at 30 Hz so will basically be just real estate to keep things open and probably wouldn't benefit that much from the card anyway. Card would eliminate a layer of complexity which is a plus. Since I already have the usb 3 adapter I'll give it a shot to try to get an idea if it will be usable.
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I'm using a DisplayLink setup on my HP notebook at work with 2 FullHD displays (which consume pretty much the same bandwidth as 4K@30Hz). Windows is able pass the workload to the GPU, so this setup is working good for me, but that USB3 solution is the only way to get more than 1 digital output from that notebook, so I didn't have any alternatives.
I tried using the same setup with a MBP, and the result was a lot more sluggish, but you might not recognize that on a 4K@30Hz screen anyway.

I think the USB bandwidth isn't critical in normal office use since the DisplayLink drivers will only send delta changes through the cable.

However, I wouldn't do that on a Mac with PCI slots. You don't need some TitanX-class GPU if you don't plan to game @ 4K, some cheap options like entry-Kepler (e.g. GTX 660ti and above) or GCN1.0 (HD 7870 and above) will support 1 or 2 4K@60Hz displays. They are not high end obviously, but still as good as (or even better) than some GPUs Apple sells in 2016 in their Macs, hooked up to high-res displays.
You should get those GPUs for less than $100 on eBay. If you choose wisely, you can even get a flashable card.

Which GPU are you using at the moment? A HD 5770/5870 is able to output 4K@30Hz through display port, so a simple DP to HDMI adapter might already do what you need.
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Thanks for reply. I'm currently using the NVIDIA GeForce GT 120 512 MB that came with the machine when I bought it used. It's driving a 27" monitor at 60Hz at 2560 X 1440 and it performs great for my work needs (web, database, Photoshop/digital photography). It's connected to monitor's female display port connector from the little squarish connector on the back of the card. I don't know much about display standards and basically just got it to work with connectors and cables available when I got the monitor a few years back. The TV will only do 30Hz in my application. Would one of the cards you suggested be able to drive two monitors with one each at 60Hz and 30Hz (2560X1440 and 4K, respectively)?

I didn't know that only delta would be sent through usb by display link drivers, which explains reports of refresh problems with some USB converters/adapters.
 
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you can get fairly cheep GPU's that will run a 4K tv, id look at Fl0r!an's advice & a nvidia card will give you audio if you want via the hdmi cable.
the usb adapter is for laptops, they tend to not work as well as a GPU.
 
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Thanks for comment and to all others who commented. The consensus opinion is compelling and I will be looking for a card instead. I would want audio through the hdmi cable so will look at Nvidia.

I am not gaming or using high fps on any of my applications. To what extent would beefiness of card effect usabiliity/performance in my case? Would I need to still use my present NVIDIA GeForce GT 120 512 MB to run the 4K TV and 27" monitor at 2560 X 1440? Should I be thinking about pulling the old card or or would using two cards be better? Would a card that would run both monitor and TV well necessarily be high end?
 
I don't think audio from video card in OS X is so cut and dry as just selecting Nvidia, even with the enabler. You might want to read the last 3-4 pages of this thread. Not all Nvidia cards will do HDMI audio. There seems to be some unclear limitations, perhaps only certain models work or Mac EFI is required. KEXT signing and SIP in Yosemite and El Capitan also complicate things.

Some AMD cards will do audio natively with no enabler, such as the Apple 5770 and 5870 cards. Unfortunately I don't think there is a comprehensive list. Those might literally be the only two.
 
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I'm pretty sure you need an EFI on the card to build the IOReg tree for the HDMI audio device (that's what the enabler kext does).
I never cared about that (in fact, I never had display with speakers :D), so I don't know that for sure.
 
I don't think audio from video card in OS X is so cut and dry as just selecting Nvidia, even with the enabler. You might want to read the last 3-4 pages of this thread. Not all Nvidia cards will do HDMI audio. There seems to be some unclear limitations, perhaps only certain models work or Mac EFI is required. KEXT signing and SIP in Yosemite and El Capitan also complicate things.

Some AMD cards will do audio natively with no enabler, such as the Apple 5770 and 5870 cards. Unfortunately I don't think there is a comprehensive list. Those might literally be the only two.

Thanks for the link. I didn't realize that patches might be required. My parameters are taking shape: a 4K card which supports audio (natively or patched) and has hdmi connector.
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I'm pretty sure you need an EFI on the card to build the IOReg tree for the HDMI audio device (that's what the enabler kext does).
I never cared about that (in fact, I never had display with speakers :D), so I don't know that for sure.

So that would mean a flashed card. The TV has better speakers than my Mac Pro so might be worth digging for.
 
I don't want to spoil your party, but I don't think you'll be able to drive a 4K TV through native HDMI in OS X, as far as I know it still lacks HDMI 2.0 support (which provides the necessary bandwidth).

An active DP1.2 to HDMI 2.0 adapter should work, but I have no idea if it can transmit audio.
 
I have 4K TV and connect it via HDMI. Only 30Hz if 4K selected (60Hz for 1080 or course). I mainly use that screen to play 4K video (during editing in FCPX), that 30Hz is good enough for the job. But if you want to use it like a normal computer, you really need 60Hz, otherwise the input lag is too much for using the mouse. TV usually have much larger input lag then a monitor, 30Hz will make it even worse. It's not just the smoothness issue, but make you can't accurately use the mouse in normal human speed.

To use HDMI Audio in current OSX, you need to disable SIP. And I can confirm that the HDMI Audio only work when I boot my 7950 with the EFI (there is a selector on the 7950, so that I can choose to boot from Mac EFI ROM, or PC ROM). Other card may react differently. But I don't think any Nvidia can give you native HDMI Audio.
 
depends what you want from your tv, i plug in a tv via hdmi to watch films sometimes & as it go's via my amp it works well for playing music.

i have a yamaha amp which has cable/blueray player/sometimes my macpro plugged in via hdmi which outputs to my tv.
the amp has some nice speakers plunged in ^^ so i can sit on my sofa and watch a film or play music via the hdmi to the amp while i work if i want.

the tv is not well placed for me to use as a display for work tho so never tried that.

from the setup im gessing your not doing intensive work & i still think a cheep gpu will work better than a usb thing & you can always use the analog or digital out if you cant get audio via hdmi.

my GTX 660 gives audio if that works, shame there's no ati sticky like the nvida one
 
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