External TB GPU chassi

Tanax

macrumors 6502a
Original poster
Jun 15, 2011
941
96
Stockholm, Sweden
I know there's been quite a few discussions about these and there are some on the market - however they are limited to PCI-e 2.0 as far as I know since the bandwidth is too low, or something like that?

So in theory, with this new TB "2", will the external TB GPU become more attractive and be able to drive a more powerful GPU-card?
 

Zeov

macrumors 6502a
Apr 1, 2011
634
113
Odense
from what i've read, yes.. but it seems nobody gives a flying F about what everyone wants, so i'm done waiting.
 

safetravels

macrumors newbie
Jun 6, 2013
19
0
I would love to see this but I really doubt it'll happen. Sony did it a while ago on one of their ultrabooks through USB 3.0 I think. My mind jumped to this sort of concept when I saw the rumours about a Mac pro refresh being 'heavily reliant' on thunderbolt while minimising internal expandability. Imagine having an external GPU that you could plug into either a desktop or a laptop, ultimate on the fly configurability, only buying the components once. It would be even better than building your own pc, although each part would need its own enclosure. A lot of people speculated that the thunderbolt display could have a dedicated gpu in it to enable gaming on a MBA for example. I would be astounded if apple ever did this though.
 

luffytubby

macrumors 6502a
Jan 22, 2008
684
0
I would love to see this but I really doubt it'll happen. Sony did it a while ago on one of their ultrabooks through USB 3.0 I think. My mind jumped to this sort of concept when I saw the rumours about a Mac pro refresh being 'heavily reliant' on thunderbolt while minimising internal expandability. Imagine having an external GPU that you could plug into either a desktop or a laptop, ultimate on the fly configurability, only buying the components once. It would be even better than building your own pc, although each part would need its own enclosure. A lot of people speculated that the thunderbolt display could have a dedicated gpu in it to enable gaming on a MBA for example. I would be astounded if apple ever did this though.
hmmm

Not sure where you are getting the USB 3 for. USB3 while fast can't handle the same load as thunderbolt.



Sony Vaio Z, got renewed without a dGPU. It skimmed the 330m which got very hot, and went for a light peak connected DVD/BR module with a GPU inside of it. The video bandwith limited it's effectiveness and capped on what was possible to get out of it. As OP mentions.

MXM is a technology that has been talked a lot about as well. Swap'n swap GPUs, like the new 15 gaming Lenovo that allows you to remove a optical drive and isert a second 650m for SLI 650 gaming. Pretty cool idea that allows a lot of freedom for individual users.



It's not a bad idea at all, but the problem is portability. You might be carrying a external HDD with you, because your on a ultrabook SSD. You might have some headphones or earbuds because the sound is atrocious, you have a beefy power supply, and you might have a mouse (if your gaming or need one for better working), you might be carrying a case for your laptop.

Suddenly, your mobile companion is dragging you down due to all these accessories that you need. to add a DGPU thing as well?

Depending on how you look at it, it might be too much, or it might be nice. What I would prefer was if there was a way to combine the PSU with this Video device. basically like having two PSU cables. one of them would be bigger and you would bring that device for when you need it, and for those times when you dont need to game/video edit/smoother performance, you could just bring the normal small PSU.

That would be really cool I think. I like the idea of removing the extreme heat of a graphics card from the gaming chasis itself. the CPU is going crazy in there already. to cool both a cpu AND a gpu under load for many hours means larger fans and more heat and more noise.
 

Mr MM

macrumors 65816
Jun 29, 2011
1,116
1
I know there's been quite a few discussions about these and there are some on the market - however they are limited to PCI-e 2.0 as far as I know since the bandwidth is too low, or something like that?

So in theory, with this new TB "2", will the external TB GPU become more attractive and be able to drive a more powerful GPU-card?
they are not limited to pcie 2.0

whats the bandwidth in a 10gbps connection?

1gbps = 0.125 GBps
pcie 2.0 x1 = reads pcie 2.0 1 lane = 500MB/s

So the math
10gbps * 0.125GBps = 1.25GBps / 500MB/s = x2.5 or 2.5 lanes

Thats for a single lane, if you use the 2 lanes of thunderbolt

2.5GBps / 500MB/s = x5 or 5 lanes

Now for thunderbolt 2.0, its 20gbps per lane, so

2.5GBps / 500MB/s = x5 or 5 lanes

5GBps / 500MB/s = x10 or 10 lanes

however the controller only allocates pcie 2.0 x4 for tunderbolt, its a standard config procedure from intel

the problem here is if you are using the internal lcd for the thunderbolt config. Thunderbolt, doesnt pass data and image on the same lane, i.e. if you do that your bandwidth will be cut in half, since there are only 2 channels.

Currently there are several chassis that support a gpu and use thunderbolt. and one just got announced its in alpha stages

http://anandtech.com/show/7040/computex-2013-thunderbolt-graphics-from-silverstone

TB 2.0 will gives us 20gpbs per lane, and real bandwidth for us to play, at x8 there is basically no performance degradation.
 

Tanax

macrumors 6502a
Original poster
Jun 15, 2011
941
96
Stockholm, Sweden
they are not limited to pcie 2.0

whats the bandwidth in a 10gbps connection?

1gbps = 0.125 GBps
pcie 2.0 x1 = reads pcie 2.0 1 lane = 500MB/s

So the math
10gbps * 0.125GBps = 1.25GBps / 500MB/s = x2.5 or 2.5 lanes

Thats for a single lane, if you use the 2 lanes of thunderbolt

2.5GBps / 500MB/s = x5 or 5 lanes

Now for thunderbolt 2.0, its 20gbps per lane, so

2.5GBps / 500MB/s = x5 or 5 lanes

5GBps / 500MB/s = x10 or 10 lanes

however the controller only allocates pcie 2.0 x4 for tunderbolt, its a standard config procedure from intel

the problem here is if you are using the internal lcd for the thunderbolt config. Thunderbolt, doesnt pass data and image on the same lane, i.e. if you do that your bandwidth will be cut in half, since there are only 2 channels.

Currently there are several chassis that support a gpu and use thunderbolt. and one just got announced its in alpha stages

http://anandtech.com/show/7040/computex-2013-thunderbolt-graphics-from-silverstone

TB 2.0 will gives us 20gpbs per lane, and real bandwidth for us to play, at x8 there is basically no performance degradation.
Yes, I wasn't too sure about what the limiting factor was but I knew that, for instance, putting a GTX Titan in your TB eGPU would be rather pointless as you would lose much of its power (due to the x4 limitation I guess?).

So with TB 2, you'd be able to put a better GPU and have little to none power-"loss", right? :)
 

B...

macrumors 68000
Mar 7, 2013
1,949
2
Yes, I wasn't too sure about what the limiting factor was but I knew that, for instance, putting a GTX Titan in your TB eGPU would be rather pointless as you would lose much of its power (due to the x4 limitation I guess?).

So with TB 2, you'd be able to put a better GPU and have little to none power-"loss", right? :)
In theory yes.
 

B...

macrumors 68000
Mar 7, 2013
1,949
2
Great to hear!
And TB 2 update is basically just another TB cable and different TB-drivers??

So say I get a TB eGPU today, I'd be able to get TB 2 on it when it arrives?
The chassis would need to be TB2 enabled as well as the TB 2 port.
 
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Mr MM

macrumors 65816
Jun 29, 2011
1,116
1
Yes, I wasn't too sure about what the limiting factor was but I knew that, for instance, putting a GTX Titan in your TB eGPU would be rather pointless as you would lose much of its power (due to the x4 limitation I guess?).

So with TB 2, you'd be able to put a better GPU and have little to none power-"loss", right? :)
yes, there is a limit that you can put in there that makes it worthwhile, we generally stop this at upper middle range series.

given the bandwidth available, we could have more powerful ones.

the problem here lies on how they use the data channels and what thunderbolt controllers equip your peripheral and machine
Great to hear!
And TB 2 update is basically just another TB cable and different TB-drivers??

So say I get a TB eGPU today, I'd be able to get TB 2 on it when it arrives?
no. youll need the new tb chip as well.
 

Tanax

macrumors 6502a
Original poster
Jun 15, 2011
941
96
Stockholm, Sweden
The chassis would need to be TB2 enabled as well as the TB 2 port.
yes, there is a limit that you can put in there that makes it worthwhile, we generally stop this at upper middle range series.

given the bandwidth available, we could have more powerful ones.

the problem here lies on how they use the data channels and what thunderbolt controllers equip your peripheral and machine

no. youll need the new tb chip as well.
Let's hope it can have more powerful GPU's then!
And d'oh! That sucks. I thought it was just updated cables. In any case, thanks for the help :)