Frying hardware or not, 7xxx support in OSX is very awesome. Now if only Apple would take the next step and give us crossfire support...
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Confirmed AMD Radeon HD 7970 GHz Edition Running on Mac Pro
- Thread starter blackwoodfx
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Thanks for the nod, Class. The worst part of this entire debacle here; I base my business and the livelihood of my family and the people that work for us around this kind of technology. I'm not flaunting any of this stuff to run benchmarks. We're using these kits every day for some seriously heavy-lifting stuff. Post visual effects, editing and transcoding 4K and 5K RAW footage, etc. We're filming on RED Epic camera systems and turning out products that get projected in theaters and will be featured at next year's NAB. We beat the heck out of these machines and did some serious multi-day burn-in renders well before I ever posted here.
And then along come the MacRumor nannies to tell me my hardware "could get fried" because they don't believe Apple built in a safety-overhead that's part of the original spec. Good grief. What I didn't mention (only hinted earlier) is that most of the boxes we're running these 7970's in ALSO have RED Rocket cards too: http://www.red.com/store/products/red-rocket
Enjoy the new hardware guys and I hope this information helps some people out there. Pretty exciting times for Mac Pro's. A really nice turn from the disappointing Summer release.
Pick up a 2012 5,1 Mac Pro, stack it with RAM, use SSD and raid stripe SSD's (VOL1 OS+Apps, VOL2 Cache, VOL3-4 R0 Data), add a USB 3.0 and eSATA card, drop in a 7970 Radeon and your machine(s) will positively chew through the heaviest that can be imagined. This configuration smokes the MAINGEAR's we invested in. Really the only thing our builds can't do is Thunderbolt. There's nothing else available right now we'd even want. So problem solved, the 5,1 is bleeding edge again. Way to go Apple!
... People have fried their boards trying to run too much power through the motherboard tracers. This is a fact. Clearly there is no safety mechanism between your 8 pin adapter and frying your motherboard. Also, what is this mythical "spec" you keep mentioning? By using the 6 to 8 pin adapter, you are operating beyond the "spec". Just because there are no warning labels on the thing saying this is a bad idea doesn't mean it isn't.
I do agree that running 75watts/connector is fine. Heck, I advocated people with modified GTX670's use the 6 to 8 pin adapter (so long as they don't OC). That's because I looked up how much power the thing uses and discovered it doesn't exceed the 6 pin spec. That doesn't mean I advocate pulling wattage through the tracers that may not be able to handle them.
I haven't done the math on the 7970, but I believe it is capable of drawing more than 75watts per connector in a Mac Pro--putting it squarely in "no man's land" and possibly getting close to the tolerances of the tracers. Who knows how long that can be sustained or at what level before something bad happens.
Maybe they just assume users will stick to the 6 pin 75 watt/cable "spec" and not use adapters/splitters. Maybe they assumed users will stick to Apple-sanctioned cards. The appearance of drivers doesn't mean Apple "blesses" this equipment and definitely doesn't mean exceeding 75watts is a good idea.
Again, we're not talking about their power supply, which I agree can handle the wattage, we're talking about the motherboard tracers.
This is a frustrating issue, but not a trivial one. The motherboard is the most expensive internal component, since Apple charges $1,200 for it. You're saying it can handle wattage above even the 75watt/connector standard without any basis in reality. The rest of us are pointing out that there is a limit and we only have a rough idea of where it is--75watts/connector is probably okay, 150watts/connector is too much.
And finally: What the heck is so wrong with an external power supply? Why are people fighting it tooth and nail and risking their hardware?
If you have any real sources for information, please let us know. Also, congrats on the new card/setup and thank you for posting. If everyone with a Mac Pro starts buying 3rd party cards, the driver support is only going to improve and maybe even MP sales will rise with people not feeling boxed in to Apples 3 horrible choices for GPU.
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So far you guys have come up with ONE person that has done this and he admitted to using dual 2x 6-pin to 8-pin connectors and over-clocking and over-volting his graphics card. Who else are these "people" you are referring to? A few people have asked the nannies of this forum to step up now and provide anyone else that has fried their LB or BP tracers using a single 6 pin to 8 pin connector. You guys are so sure this absolutely must happen -- well it's in your hands to prove it then. I've got a studio that's been running on this gear for a few weeks now and everything I've got says you guys are a few warning labels short of a full deck.
It's one 6 pin cable pre-spec'd for 150w with two extra grounding wires using a 6-to-8 pin connection. You guys are terrified of this and it has crossed the threshold from 'odd' and has moved fully into 'weird'.
*mind blown* You guys are hypothesizing it can't... I'm running multiple proofs it can. I've also provided the actual spec used on the same components for an HP product, built by Intel -- the very same as the MP's. No basis in reality? Flip that script.
...Wow. I'm outta here. And goodnight.
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With the hundreds (thousands) of users here I like to here an "Aye" from everyone who has fried a logic board trace from using a 6 to 8 pin adapter.....
Please speak up !
I don't think many have tried it. And those who have put >225W GPUs in their Mac Pros have used external GPU PSUs for safety...
Wow, your an engineer too? No way!!!
Sources for the following (Actual Specifications)
75W slot limit: http://www.pcisig.com/developers/ma...c_id=6d37ec2f8543fc1f9d8ace6264d08b469f57e5f1
6/8-pin design:http://www.pcisig.com/developers/ma...c_id=fa4ec3357012d69821baa0856011c665ac770768
Also: http://www.playtool.com/pages/psuconnectors/connectors.html#pciexpress8
The PCI-E slot is rated for 75W draw.
The 6-pin connectors are EACH rated to 75W with three 12V and three grounds. Max Amps ≈ 2, so: 12 x 3 x 2 ≈ 75W
The 8-pin connectors are EACH rated to 150W. with three 12V and five grounds. Max Amps ≈ 4, so 12 x 3 x 4 ≈ 150W
WITHIN SPECIFICATION TOTAL IS 225W. PERIOD.
So, the 7970 is rated to draw, at stock clocks and voltages, 275W MAX.
In reality it is pulling less than that, so for the sake of argument lets call it 250W.
From reading the above documents, it seems that the manufacturers have the ability to draw up to the limit from any combination of the three sources as they like, but for the moment I am going to assume that they pull the max from the slot and the 6-pin.
So, 250-150 = 100W for the 8-pin.
100W over 3 traces ≈ 33.3W each which is 7.3W over spec.
33.3/12 ≈ 2.775A
Actual rating is 2.083A, so you are potentially drawing 33% more power through those traces than the spec.
So really, given safety margins and what-not that is almost certainly going to be ok.
If you really want to show off you should hook up a ammeter to each of the 12V traces to see what they are pulling.
I'm half tempted to find out myself!
My reading of the thread is as follows:
- You post that it's working for you.
- Someone questions your math on the power draw (which was incorrect).
- I post that our standard recommendation is to use an external PSU for cards that require more than 225W.
- You start the name calling.
Do you have a link to the spec for the HP/Intel product? I'd be interested to see it.
Again, all I'm seeing anyone do is post that we've typically been cautious about using cards that require more than 225W, period. Given that (up until now) nobody has anything approaching a hardware spec for the Apple motherboard, I think some amount of caution has been warranted, since not everyone can afford to replace their machine if something does go wrong.
If you have definitive proof that it's okay, I think the community here would love to see it. The fact you're being such an ass about it isn't really helping the discussion. I'm happy to be proven wrong and shown that it's perfectly safe to draw 150W from the motherboard connectors. That opens up a ton of possibilities for Mac Pro cards (e.g. now you can drive 2 cards that require 225W etc).
Again, all I'm suggesting is that we've been somewhat cautious in the past when using cards with 8-pin connectors. If you have the technical data to prove that it's totally fine to use these, great, we've all learned something. I don't think anyone is arguing that you won't be able to drive these cards for days or weeks, what we're concerned about is the potential for damage over a period of months or years.
I've been following these video power threads a long time and I can only think of the one example. In the example it was 2x8-pin, and even then it reportedly worked fine until the owner then went on to push it even further by overclocking and overvolting.
If there are other examples, I am very interested in reading about them, but I have searched and am unable to find them.
silly question, where is it stated a mac pro is only able to deliver 225W to a single gfx card?
Because bunging two 5770's in (one of apples options) is a 300W total option, so you're only really messing with a difference of 75w being pushed to two pcie slots, instead of 150w to one... & pcie power draw is measured by bus too, as I understand it.
However, it's certainly not an Apple approved or recommended option, but a lot of stuff isn't...
Either way, i'm waiting until either an ati 79xx or nvidia 6xx option supports bootscreens... Would another option be to link one of those 75W connectors to the macs PSU? not sure whats free or easily accessible on there as not had my mac to pieces (well not to that degree anyway!)
Nox
Because bunging two 5770's in (one of apples options) is a 300W total option, so you're only really messing with a difference of 75w being pushed to two pcie slots, instead of 150w to one... & pcie power draw is measured by bus too, as I understand it.
However, it's certainly not an Apple approved or recommended option, but a lot of stuff isn't...
Either way, i'm waiting until either an ati 79xx or nvidia 6xx option supports bootscreens... Would another option be to link one of those 75W connectors to the macs PSU? not sure whats free or easily accessible on there as not had my mac to pieces (well not to that degree anyway!)
Nox
This was explained earlier, and in several of the links about PCIe power.
PCIe slots deliver 75W each. Each 6-pin power cable is spec'ed for 75W. 8-pin power connectors are spec'ed at 150W.
So, you can drive 75W (slot) + 75W (cable) + 75W (cable) = 225W for one card that has 2 connectors. Since the 5770 only has one connector, you can drive two of them:
- Card one = 75W (slot) + 75W (cable)
- Card two = 75W (slot) + 75W (cable)
Again, this is all based on the PCIe power standard, which states that 6-pin power connectors are rated at 75W.
Hence my confusion, I thought 4x75 was 300, not 225
Nox
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However, it shows the PSU is certainly more than capable, it's 980W isn't it?
I would be much happier if a cable was run from the psu directly to the 8 pin port on the gfx card...
Nox
This thread is amusing. I think what people are missing here is the fact that the OP believes, hypothecially, that Apple's official specs of 225w are set lower than the actual safe operating levels as a sort of "buffer" to make sure customers stay well within safe limits. Whether that's true or not, I can see where he's coming from as Apple has long been known to publish official specifications that are much lower than actual safe limits (i.e. official max memory specs being 25%-50% lower than what the machines are actually capable of supporting)
Also, web forums and feedback/rating sections are always full of the angry and disappointed. We're always more likely to hear from the guy who fried his hardware with a GTX 580 than the people who have been using it safely for extended periods of time.
Regardless, this thread will be a great resource for future readers. If the OP fries his machines with the 7970's, it's probably a good bet that 250w+ is a bad idea. If he comes back a year later and everything is still running fine, it's likely that ~250w will be fine for most users.
Also, web forums and feedback/rating sections are always full of the angry and disappointed. We're always more likely to hear from the guy who fried his hardware with a GTX 580 than the people who have been using it safely for extended periods of time.
Regardless, this thread will be a great resource for future readers. If the OP fries his machines with the 7970's, it's probably a good bet that 250w+ is a bad idea. If he comes back a year later and everything is still running fine, it's likely that ~250w will be fine for most users.
I think you all are missing something here...
The HD7970 non-GHZ was measured to be around 200 Watts in actual power draw. The HD7970 GHZ draws about 20 Watts more. That is 220 Watts which is within spec. The 8 pin is only really necessary when overclocking.
Source: Guru3D
The HD7970 non-GHZ was measured to be around 200 Watts in actual power draw. The HD7970 GHZ draws about 20 Watts more. That is 220 Watts which is within spec. The 8 pin is only really necessary when overclocking.
Source: Guru3D
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According to hwcompare.com the 7970 is rated at 250w max TDP, they do not yet have the GHZ edition listed.
Both the GHZ and non-GHZ version have 250 watt max TDP. However that is not what the cards actually draw under load.
Thanks for sharing. This is great news.
BTW, perhaps your particular 7970's under this particular work load are indeed within the current draw limits of the main board. Just because a card is rated for a given TDP doesn't mean it will draw that amount of current all the time under all work loads.
Very true, just explaining the position of those who say it won't work: that there is a chance the card could draw 250w at some point and fry the LB, the graphics card, or both.
Like I said, it's mostly just a wait and see situation whether this works out for the OP or not. He seems to be running extremely high loads on his machines without issues yet, so I'm interested to see what happens in the future.
Steam & DVD
I know the 6870's work without flashing but they didn't support Steam or DVD playback. Do you know if the 7970 behaves the same?
I know the 6870's work without flashing but they didn't support Steam or DVD playback. Do you know if the 7970 behaves the same?
Here is another good review of the GHZ power usage.
http://www.techpowerup.com/reviews/AMD/HD_7970_GHz_Edition/26.html
Measured directly from PCI-E power connectors and bus. Average wattage under load is 209w. Peak wattage was 238w. Max wattage is 273w. Now before people freak out over 273w that is measured when running FurMark. The GTX570 probably exceeds 250w in Furmark. In fact Nvidia made it so that their driver will throttle the card when Furmark is detected...
http://www.techpowerup.com/reviews/AMD/HD_7970_GHz_Edition/26.html
Measured directly from PCI-E power connectors and bus. Average wattage under load is 209w. Peak wattage was 238w. Max wattage is 273w. Now before people freak out over 273w that is measured when running FurMark. The GTX570 probably exceeds 250w in Furmark. In fact Nvidia made it so that their driver will throttle the card when Furmark is detected...
Right, nobody is questioning whether the PSU itself is powerful enough. The issue is the fact that the PCIe power cables connect directly to the motherboard, and thus power is delivered via traces on the motherboard. If you fry those, you need a new motherboard. Nobody is questioning the fact that there's going to be some headroom above the rated 75W for a 6-pin connector. The issue is how big is that headroom, and whether it's literally more than double (since an 8-pin cable is allowed to draw 150W, and I'm assuming you'd want some headroom on top of that).
My position has always been a cautious one. Personally, I have actually run a GTX 580 with a converter cable in the past, for some simple testing. However, I don't feel comfortable telling everyone on these forums that it's perfectly safe to do so, and that you don't need to worry about the fact that the 6-pin connection is only officially rated at 75W. If the OP has documentation that proves the Mac Pro motherboard can safely deliver 150W or more via those connections, then great, we've all learned some very valuable information. Otherwise, I'm going to continue to be cautious, particularly when making recommendations to others.
Will the nannies that keep repeating the same thing please exit this thread. You've crapped on this post well enough and everyone has seen your warning stickers. Thanks.
The very same LB/BP's you guys keep suggesting can't carry 150w already route 300w to the PCI's (single trace from start, then branches) and another 250w to the Xeon's. And those channels also have a fault tolerance. Further, 6-pins are rated for 150w each with the 3x 12v rails. I've been running it under heavy load and with multiple platforms and for a few weeks now. Last, I'm posting this message on one of those same platforms while I crunch down a particle system for a vfx shot.
You don't want to a run a 7970 on your box, fine. Please leave those of us that do well enough alone now. I'm sure there's something else sharp and pointy you can go complain about.
End sum: 7970 pulls 75w from 6-pin, 150w from 6-to-8 pin, and 75w from the PCI slot. That's 300w combined. As I stated from my first comment, this card tops out at around 250w which is 50w under that thresh. I made this perfectly clear pages ago and the only thing the nannies are still complaining about is they can't reason to believe that 6-to-8 pin is working and safe. Good grief...
The very same LB/BP's you guys keep suggesting can't carry 150w already route 300w to the PCI's (single trace from start, then branches) and another 250w to the Xeon's. And those channels also have a fault tolerance. Further, 6-pins are rated for 150w each with the 3x 12v rails. I've been running it under heavy load and with multiple platforms and for a few weeks now. Last, I'm posting this message on one of those same platforms while I crunch down a particle system for a vfx shot.
You don't want to a run a 7970 on your box, fine. Please leave those of us that do well enough alone now. I'm sure there's something else sharp and pointy you can go complain about.
End sum: 7970 pulls 75w from 6-pin, 150w from 6-to-8 pin, and 75w from the PCI slot. That's 300w combined. As I stated from my first comment, this card tops out at around 250w which is 50w under that thresh. I made this perfectly clear pages ago and the only thing the nannies are still complaining about is they can't reason to believe that 6-to-8 pin is working and safe. Good grief...
Honestly, if you're doing Pro work and have the time/passion to experiment with your hardware, then all the power to you.
The reason I personally moved to Apple from Windows was because I didn't want to be my own tech support. I just wanted things to work, at least 90% of the time. As always, things happen when you push these machines. However, I like the fact that you can treat Apple products kind of like a car lease...where you use it for a few years, and it "expires" so you don't even need to upgrade, just sell it (it retains good value) and just get a new one. Of course, we all know in this case Apple has forgot about the Mac Pro (things are looking positive for 2013, though.)
But overall, I am glad there are people like you out there that want to experiment. I for one do not want to experiment with things and make it work, I just don't have that kind of time to worry about hardware when I am just out doing creative work, especially since I don't have my own IT department to take care of that.
The reason I personally moved to Apple from Windows was because I didn't want to be my own tech support. I just wanted things to work, at least 90% of the time. As always, things happen when you push these machines. However, I like the fact that you can treat Apple products kind of like a car lease...where you use it for a few years, and it "expires" so you don't even need to upgrade, just sell it (it retains good value) and just get a new one. Of course, we all know in this case Apple has forgot about the Mac Pro (things are looking positive for 2013, though.)
But overall, I am glad there are people like you out there that want to experiment. I for one do not want to experiment with things and make it work, I just don't have that kind of time to worry about hardware when I am just out doing creative work, especially since I don't have my own IT department to take care of that.
At some point, I bought into that Apple mantra too. Then I quickly realized it's a load of bunk.
For starters; Apple TV never works correctly. There are constant software bugs and connectivity niggles and after snapping up three generations of hardware for multiple televisions across home and studio, Apple announces "it's a hobby". Nice. How about the fact that the iMacs have, for multiple generations now, not matched the hardware dimensions of the Apple LED Cinema Displays? You need to buy an after-market stand to get the monitors leveled for multi-monitor mini-seam transitioning.
Or what about the Airport Express modules that would limply hang off the wall with their prongs exposed, luring children (worst-case) or would simply fall off the wall with the slightest bump (common)? Or how about the fact that the current generation of Airport Extreme and Airport Express hockey pucks are not compatible when attempting to use the Express to expand a network (even though Apple claims they are)? What of the fact that every single 30 pin iToy connector I've ever seen frays at the plug? Or the fact that Apple had to replace all of the original 5v cubes? Or that the first and second generation Apple Garage Band apps had a bug that only allowed monaural output? Pretty significant when you're talking about a music program... Or that Apple bought Logic and drove the product into the ground (which they also did with other major professional tools)?
Remember the iPhone antenna-gate problems? How about the first generation iPhone that had a "lock screen" that didn't actually lock/secure anything? Did you ever use the iPhone 4.* release that caused visual voicemail to not display for up to 30 seconds each time?
I once had an iMac DVD jam in the side-screen slot load. That DVD and the HDD inside of the iMac contained an unreleased album from a major recording artist, plus unreleased/unapproved video footage from a music video rough. I called Apple Support and after attempts at software troubleshooting, they told me it was not possible for me to fix this by myself. I would need to take the iMac into an Apple store to fix it. Because Apple neglected to include the paperclip force eject hole that every other computer on Earth has -- presumably this was because Apple didn't like the aesthetics of a pin hole -- I had to bring everything into an Apple Store to fix this and they would need to bring the computer into the back room (where I'm not allowed) to perform the work. Nope. Couldn't risk it. Had to do the disassembly and dirty work myself. All.. to... eject... a DVD. The drive never jammed again and I made sure to only use external drives for vital work.
Have you ever downloaded an album from iTunes that was corrupted and then had to email Apple and ask for a re-download? I have. Did you ever need to contact Apple support because you had reached the limits of iTunes activations and needed to reset all of them so you could use iTunes again? Yep, been there.
How many times in a week do you need to provide your administrator password, sometimes even multiple times in a row. I distinctly remember Apple making fun of Microsoft for this (which no longer happens in Windows since 7, by the way).
Ever max out your RAM shopping with Apple only to find out later, the hardware can safely support much more but Apple inexplicably won't sell or advertise that? That's fun. And expensive.
Or how about all of us MacBook Air buyers that bought the first generation hardware and only found out later, after light-weight use (browsing internet or playing music) the thing would heat up on battery and the second processor core would shutdown. Nice. Great design there. Again, expensive.
I've also got an iTunes-bought Disney movie I bought for my daughter that inexplicably pops French credits and then de-synchronizes the vocal track in the middle of playback. I've emailed Apple about that and never heard a word back. But because the video file is 'in the cloud' via iTunes Match, it can't be fixed on our end.
Or that Apple Maps doesn't work as-well-as Google Maps and even though they had a license that ran until next year, they pulled the plug in the interest of competition only.
There are countless more. These just off the top of my head. "It just works" is a marketing bullet point.
But hey, these 7970's do 'just work' and no one here wants to believe that...
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You seem bitter. I for one believe the 7970's work perfectly in the Mac Pro and thank you for the info.
WOW. If I had even 10% of that happen to me, I wouldn't have a single Apple product any more. You are either exceptionally forgiving, or your livelihood depends on Apple products!