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The reason i ask this is cause in nando4s Sandy Bridge eGPU laptops list the MBP 13 and the MBA are listed but the MBP 15 is not. Is this because it already has a internal dGPU?? Or will it possible to have a thunderbolt eGPU with it??
I would say ask him? I have no idea how you would even get it running on a MBP13" nor MBA as there is not expressport or easily acessable mPCIE. the OLD MB with an expresscard I have seen done. you would also need to have firmware support I believe from Apple
is there a TB to PCIE adaptor already? I must have missed that.
the theory is great but I would like to see it tested as Apple is notorioous for hanging up such things in their firmware.
in wondows I could see MM's point in windows as the DGPU can not be disabled and All Macs tend to hate 3 video cards ( even Mac Pro's )
YEah, even i read on Nando's thread that Thunderbolt should be able to give about 80% of true performance, I am happy with that. As long as it is faster than a Express card slot. I plan on using it with a GTX560 Ti or a GTX570.
Sonnet indicate the Thunderbolt port is two 10Gbps channels
here, which would be internally wired as two x2 2.0 ports to the Series-6 chipset. If Apple wire those 4 lanes sequentially as port1-4 or port5-8 AND provide a mechanism to switch it in the bios then it could run x4 2.0 (20Gbps). If not then it may well be that a x2 1.0 Optimus setup via exprsscard slot (5Gbps + pci-e compression) will provide the same performance as a 10Gbps Thunderbolt port. It would be poor form on Apple part if 20Gbps wasn't possible.
If anyone has a MBP with Thunderbolt port, can they run AIDA64 and grab a listing of the southbridge pci-e ports like
this, ensuring the PCI Express controller listing is shown? Then also check their 'bios' to see if have any options to set a x2 or x4 Thunderbolt port, might be called 1-channel or 2-channel?
I believe Mr.MM has a MBP 13.
Hey Nando was there a reason that you did not include the MBP 15 in your list?? I mean if a ThunderBolt eGPU works with the MBP 13 then it should also work with the 15inch model with the 6750m right??
The
Sandby Bridge notebooks for an eGPU list originally had only thin-and-light systems. I've added a few select lightweight 15" options as well. Macbook Pro 15 has now been added.
Well that makes sense ofcourse, people who go for eGPU want a thin and light. The only reason i am considering the MBP 15 over the 13 is cause the res on the 13 is too low for me, wish it had 1440x900 like the MBA(whose processor wont cut it for me).
Good to hear that an eGPU may also work with the 15inch model.
Hey Nando here is something about the Thunderbolt and the PCi-e lanes it uses from AnandTech -
AnandTech - The MacBook Pro Review (13 & 15-inch): 2011 Brings Sandy Bridge And would the info Nando is looking for be available through the System Profiler in Mac, Mr.MM might as well look into it, I really have no idea.
Even I am thinking of getting the MBP cause of the ThunderBolt eGPU. What really concerns me is that in Windows there is no trace of thunderbolt while using BootCamp, does this mean a thunderbolt eGPU would not work in BootCamp?
the latest firmware gave support for windows on bootcamp, so be confident on that. There are still some issues, like the pc wont sleep, also this is per anandtech.
I have looked in the system profiler and there is no info regarding that, only the firmware version, and the status of the port.
Its not apple to allow, but us to code something, people on the windows world face some difficulties sometimes doing the egpu thing
actually no, windows machines pack that same gpu, or nvidia similars, only achieve that battery life with extended batteries and switchable gpus.
its is really a shame that customizations or actual engineering like what happens on business machines is not applied to those cases, so yeah its pitful at best to have the same battery life as machines that uses some form of switching
now on the thread, I havent been able to identify what ports are wired to the thunderbolt port, however there is one good news, even my mbp 13 posses a mux in the gpu... so we may be able to wire the thunderbolt port to display the image on the notebook lcd, no external monitors required
Of course it does, because Express card is barely 1x of PCIe. If it where 1 lane of PCIe v3.x, the Express card slot would have almost the same bandwidth as thunderbolt. It is far much better to get an Express card slot with actual 4x or more lanes, which would give significantly more bandwidth than thunderbolt.
10-20Gb/s is not that much, considering typical current PCIe speeds roam about 64Gb/s for the old v2.0 PCIe. v3.x is even higher. It is a lot, however, when compared to the rest of ports (USB etc) available on PC.
It's a nice port with high memory bandwidth compared to many other ports available in PC, but for graphics card, its far easier(and faster) to make a higher lane count express card for an eGPU.
well according to some reviews, x4 is an acceptable bandwidth, most games suffer a penalty of 1-10%, being some ports the cause of high consumption of bandwidth and where staggering differences where felt, something around 50%
I did some tests right now, and nothing is conclusive as of yet, but it seems that the pcie ports that the thunderbolt is going to use are the ports 4-8, thus raising the possibility that all are sequential.
What they've done is split the x16 root port into two x8 ports (0:1.0 and 0:1.1). The first has all 8 lanes connected and is used to host the dGPU (HD6750M). The second is the Thunderbolt port with only 4 of the 8 lanes connected as highlighted below.
So Thunderbolt is x4 2.0 as I expected it to be.
Problems? See this thread at archive.org.
