Let's see about that when it's released, but I agree that it's good to take anything a vendor says with a grain of salt, including you.
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People Who Complain About the New Mac Pro Misunderstand It
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Let's see about that when it's released, but I agree that it's good to take anything a vendor says with a grain of salt, including you.
We really need a laugh button rather than just replying to do a smiley.
BTW, who are you trying to convince? Those who drink your koolaid will agree with you, those who do not will not. You can say all you want and nobody will change sides.
Well I am sufficiently lost. But that was kind of my point.
E5 Xeon. AMD FirePro. 1866MHz DDR3. This should be enough to draw conclusions. You don't need all the info from Apple. They just obfuscate things. They can't magically alter what these components can and can't do. All they can do is alter the mobo and squeeze out options. Which would be nice info to have.
So we should listen to a vendor with an income stream at risk? Sounds reasonable to me.
Honey you're drinking the Apple cook-aide. Clearly, a TB (v1) is a duplex 10 GBits/s medium on a PCIe 4x lane. I am not an engineer but, I certainly realize the speed I can get on a PCIe 16x vs PCIe 8x vs PCIe 4x... you get the point. I used to run CUDA on a PC with one PCIe 16x video card and three PCIe 1x Radeon cards. Needless to say, the thoroughput on a PCIe 1x is not worth high-performance computing. I'm sure PCIe 4x is faster but many of us would like to exploit as much of our systems as possible. I'd rather run compute on PCIe 8x (available on 2010, 2012 Mac Pro, since there's technically only one PCIe 16x lane on mobo) cards than PCIe 4x.
Why do you think there hasn't been any external video card options for TB? I'd sure love to see the mythical eGFX cards conceptualized by many when TB was first released. Only things we've seen are audio cards and video capture cards through TB. I'm not sure if TB2 will have enough electrical oomph to drive an eGFX card, but here's to hoping.
So I'm not sure where you're getting your 60 PCIe slots right now. Besides, TB is a serial connection, much like USB so you lose bandwidth the more devices you connect (although it doesn't seem to be the case, but I can't say for certain). Given the high-bandwidth available on the medium, the difference might be negligible, but still there nonetheless. If it were a parallel connection, then maybe it'd be more forgiving. To your point, 6 TB (slots) x 10 devices (per slot) = 60 PCIe 4x lanes (?). If I were not so technically inclined, I'd say "gee whiz I want this machine now! it's even more powerful than some of Google's stand-alone cluster right now! At this point, who'd need Infineon fiber cards with the uber-duper fast duplex connection?"
Let's suppose the Mac Pro has six TB controllers to share thermal allowance with the rest of the device... 60 devices will certainly heat the system up quick. Just transferring gigabytes of data on FW800 on multiple drives at the same time certainly heats up my system. At 60 devices attached to TB and max bandwidth, you'd certainly have an "incinerator pro". There goes $2000 up in smoke (plus the cost to get the 60 devices you are suggesting).
Contrary to your point, I think the new Mac Pro is THE "one size fits all", and it's a huge ass one-size-fits-all for the so-called "prosumer" segment of the market. It's a downgrade for us real "Pro" users.
Just my 2cents.
http://upload.wikimedia.org/wikipedia/commons/b/be/Thunderbolt_Technology_model_1_E.png
Actually, I'm a software engineer, but my musings on Electrical Engineering is very basic at best...
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The ONLY way the "vendor" macvidcards income stream would be at risk would be if suddenly, EVERY current Mac Pro in the entire world spontaneously combusted.
Just because the guy has a business flashing PC video cards to work in Mac Pros does NOT, I repeat: NOT make his opinions of the iTrashcan invalid.
In fact, his opinions are the majority, no matter how hard you want to convince yourself and others it isn't.
Sorry my fingers tripped on your Thunderbolt cord. Oh wait, you mean there's no MagSafe on Thunderbolt? Oh you lost data because your external SAS crashed? Ooops...
Likely the same place that mainstream PC boards get their 4+ physical slots when the CPU and IOHub have no where near that many lanes to provision the slots with. Namely, stack physical slots up behind a giant hierarchy of PCI-e switches ( via the TB controllers ).
it is not so much that it is serial but that the PCI-e portion of Thunderbolt's functionality appears as a switch. The TB network builds a tree of switches. But yes the switches serve to dilute the bandwidth available at the leaves in the tree as more are added.
Thunderbolt ports do not provide additive bandwidth.
It is somewhat like USB but the network overhead and hub/switching latency is much lower. Even over USB 3.0 which substantially reduces the overhead on the SuperSpeed wires.
It is not so much loosing bandwidth as having to divide the same pie up into smaller pieces. Add more folks to feed with single pie... smaller pieces all around.
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The ONLY way the "vendor" macvidcards income stream would be at risk would be if suddenly, EVERY current Mac Pro in the entire world spontaneously combusted.
Complete male cow droppings. The income stream is at risk because the number of slots out there to fill is about to go down long term. Imploding overnight has diddly squat to measuring the real risk factors here.
Again misdirection. It does make them biased. He has a vested financial interest in there being an increasing number of Mac Pro PCI-e slots out on the market.
His inaccuracy rate is way up from his normal track record.
The majority of very active posters perhaps. Whether that is the majority of Mac Pro users is questionable.
Let's do the math:
* one (1) PCIe (v3) 1x lane = 10 Gbps duplex
* TB (v1) is roughly equal 40 Gbps (aggregated) which means two PCIe (v3) 1x lane PER DIRECTION
* double that for TB (v2) at best
Even then, the last I checked, Thunderbolt controllers can't physically be aggregated. Aggregation ONLY OCCURS on the controller level so you can't plug in six (6) TB2 ports to aggregate. Unless this has changed...
Don't even know why I'm bothering to try to make sense of all these numbers. They're just spin... but hey good luck on your purchase if you do decide to buy a trash can pro.
What professional external interconnect have magsafe? Usually the opposite is true and it comes with a locking mechanism.
Please link us to something I said that was inaccurate?
True but unfortunate doesn't count.
You're absolutely right, there's no GPU that's going to work well, if at all over TB.
But it's hard for me to see that the current Mac Pro offers more expansion for someone that wants dual high end GPUs... consider...
If I want a pair of modern GPUs in my 2009 Mac Pro, I not only need a supplemental Power Supply (making this anything but plug & play), but I also end up with only a single x4 slot accessible afterwards since the second double-width GPU is going to cover one of the x4 slots. So if I want to add both PCIe SSD storage and USB 3, I'm screwed.
It seems to me the new Mac Pro offers folks that want dual high-end GPUs much better expansion options than the current machine. I can have both USB 3 and PCIe SSD (without adding anything). My audio interface is already external. My offsite backup is already external. All I need is to put my 3TB archive drive in a USB 3 enclosure and I'm done.
So while you'd be accurate in saying you can't put 6 drives inside the new Mac Pro, you'd also be correct in saying you can't put dual high-end GPUs, USB 3, PCIe SSD and still have three x4 slots left for additional toys in the current Mac Pro.
It's a lot easier to find a home for HDs than it is to fit all that other stuff in the current Mac Pro.
BTW, there's a lot of confusion (not necessarily on your part) about what TB is and is not. Each TB controller in the new Mac Pro (and there are three) multiplexes 4 PCIe 2.0 lanes with a Display Port signal. TB2 merely combines what was two TB1 10Gbsp channels into a single 20Gbps channel to support DP 1.2 capable of driving a 4K display. The only net benefit of TB2 over TB1 is the 4K display support. There is no added throughput for PCIe data. So if you account for it simply based on number of PCIe lanes brought to the ports on the back of the new Mac Pro, there's still the equivalent of three x4 slots available AFTER your dual high-end GPUs, dual PCIe SSDs, and 4 USB 3 ports.
I didn't claim the RAM is soldered on, I said it was in the laptop range. The SSDs are a different connector to standard (PCIe not SATA) and the GFX cards are completely different to standard desktop ones in shape and connection.
All this screams lack of transfer from the cheaper mass produced PC market. Exactly what Apple have done with MBP and iMac internals...
But, as you say it isn't out yet so we can wait and see if this prediction has any accuracy.
I hope I'm wrong on all counts but I don't think so, more's the pity.
Wow, wait a second. So the old Mac Pro only had 2 16x slots and 2 4x slots? And this is what people are seriously fighting for?
This has got to be a joke. The new Mac Pro will come with the exact same port bandwidth as the last gen with extras. 2 16x slots for each video card and 6 4x slots over thunderbolt, and several mini pci express slots for wifi and storage. And if you want to run anything that requires huge power you still have to buy the exact same optical bay mounted power supply.
Apple just did everyone a huge favor, we are literally getting at least the exact same port configuration we had plus a bunch of extras with better core system performance.
You found his info so informative, see if you can use it to correct your math.
Six TB ports does not mean six x4 lane, since each *pair* of TB ports shares a controller... "Unless I am wrong (and I am *never* wrong), they are headed dead into the fire swamp."
Regardless of the controllers, each port supports 20Gbit/s in each direction.
You're not wrong yet.
Each controller gets 4 PCIe lanes and a pair of ports share that. Yes, but that 20Gbps is the multiplex of x4 PCIe 2.0 lanes and display port. 4 PCIe lanes can effectively carry 4Gbps each or 16Gbps together. Display Port uses anywhere from around 6Gbps (27" ACD) to 16Gbps (4K).
The good news is that with TB2, it combines what was two 10Gbps channels into a single 20Gbps channel which may explain some of the recent enthusiasm over TB breaking the 1300MB/s barrier. If TB1 was limiting the PCIe to just one of those 10Gbps channels, that would explain the bottleneck of around 1200-1300MB/s. Now with no TB bottleneck on the PCIe data, properly engineered TB2 peripherals should get the full x4 bandwidth if a display is not eating into the bit budget.
Well, if that's a true fact, then two TB ports will max at 5GB/sec, and six will max at 15GB/sec.
I'm going on record to state that is incorrect, due to the bandwidth being shared by the single controller behind every two TB ports. Can someone prove me wrong?
Well actually it's worse than you think on both systems
In the current Mac Pro its believed that the top two x4 slots actually share 4 PCIe lanes through a switch as there just aren't enough lanes in the current chipset to support each slot having dedicated lanes.
On the new Mac Pro, each of the three TB controllers is allocated 4 PCIe lanes which is switched between the two ports connected to it.
So if you just compare x4 expansion options between the current Mac Pro and new Mac Pro, you have the current with two slots sharing 4 lanes and the new system tripling that with three pairs of TB ports each sharing 4 lanes.
Since the Thunderbolt 2 spec aggregates 2 links to achieve 20Gbit/s it seems reasonable to believe that Falconridge either only have one port, or takes 8 lanes. How else would the spec make sense, each port would eat all bandwidth. I have not seen any published information about Falconridge yet however. But… If the bandwidth is shared once a second connector is present then that's a different story, we'll see I guess.
TB2 combines the two links into one so it can support Display Port 1.2 and 4K displays. Nothing about the PCIe lanes or bandwidth has changed other than perhaps a removal of an artificial cap of 10Gbps previously the result of having two links instead of one.
Here's a good brief overview of TB 2...
http://www.anandtech.com/show/7049/intel-thunderbolt-2-everything-you-need-to-know
Well that's what I just said, the consequence of that on a controller with two ports is what? If each port aggregates 2 links in each direction, it's not enough for two ports per controller, unless it's only enabled while one port is in use.
Anandtech said: