Express Card TP W540 GTX 970 ?

[Gogito]

So I'm using a Lenovo Thinkpad W540 with a core i7 4700 and Quadro K2100M. I'm planning to use my Express Card slot to set up a eGPU with a GTX 970. How will this fare out ? Will the 970 be bottlenecked and how much ? And is there a better card for my system instead ?

 

I'm not really sure whether it's got Express Card 1.0 or 2.0 though.

 

This is the kit I'm gonna use

http://m.banggood.com/Expresscard-Version-V8_0-EXP-GDC-Beast-Laptop-External-Independent-Video-Card-Dock-p-1009976.html

 

Here's the specs of my W540

http://shop.lenovo.com/us/en/laptops/thinkpad/w-series/w540/#tab-tech_specs

 

Thanks in advance guys !

[Yukikaze]

Is there a reason why you don't want to use a Thunderbolt solution? If you have the money to spare, and can obtain an Akitio Thunder2, it would be definitely superior.

[Gogito]

9 hours ago, Yukikaze said:

Is there a reason why you don't want to use a Thunderbolt solution? If you have the money to spare, and can obtain an Akitio Thunder2, it would be definitely superior.

 

It's only a TB 1 port, will it be better ?

[Yukikaze]

46 minutes ago, Gogito said:

 

It's only a TB 1 port, will it be better ?

 

Yep. If your Expresscard is PCIe Gen2 x1, it is the equivalent of PCIe Gen1 x2. Thunderbolt 1 is a PCIe Gen1 x4, so it has twice the bandwidth than the Expresscard solution. If your Expresscard is PCIe Gen1 x1, then Thunderbolt 1 will have 4 times the bandwidth. In either case, it is quite a bit more breathing room for your card to work with.

 

Also, there is also the Thundertek/PX, which is a Thunderbolt1 solution and cheaper than the Akitio (keep in mind that it doesn't come with a TB cable, but a TB cable can be found on Ebay for 20-30$ - I bought one last week for 19.50$). You will be modding either device to work with a GTX970, so you should be able to save some money on the cheaper Thundertek (unless shipping is going to kill that off). I suggest you browse the guide forums to see both solutions used.

Edited May 13, 2016 by Yukikaze

[Gogito]

Just now, Yukikaze said:

 

Yep. If your Expresscard is PCIe Gen2 x1, it is the equivalent of PCIe Gen1 x2. Thunderbolt 1 is a PCIe Gen1 x4, so it has twice the bandwidth than the Expresscard solution. If your Expresscard is PCIe Gen1 x1, then Thunderbolt 1 will have 4 times the bandwidth. In either case, it is quite a bit more breathing room for your card to work with.

 

Also, there is also the Thundertek/PX, which is a Thunderbolt1 solution and cheaper than the Akitio (keep in mind that it doesn't come with a TB cable, but a TB cable can be found on Ebay for 20-30$). You will be modding either device to work with a GTX970, so you should be able to save some money on the cheaper Thundertek (unless shipping is going to kill that off). I suggest you browse the guide forums to see both solutions used.

 

Thanks a ton. I'll go with the ThunderBolt route then. What about the bottleneck then ? How bad would it be for a 970 ?

[Yukikaze]

3 minutes ago, Gogito said:

 

Thanks a ton. I'll go with the ThunderBolt route then. What about the bottleneck then ? How bad would it be for a 970 ?

 

It is a hard question to answer, to be honest, since it is highly dependent on the application/game in question. For example, synthetic benchmarks often do not care about PCIe bandwidth, but some games are more sensitive to the reduction. It is also typically the case that the higher the resolution, the less the bandwidth matters (simply because the card needs more time to crunch the data, so there is less of a need to keep it constantly fed with more).

 

You can also check out this article at TechPowerUp. It uses a GTX980, but your scaling should be in the same ballpark. The result you are interested in is the "x4 1.1" row in the graphs, since that is the equivalent of a TB1 link. It shows a lot of results for specific games and also an averaged percentage of max performance at the summary page here.

[Gogito]

On 5/13/2016 at 10:32 PM, Yukikaze said:

 

It is a hard question to answer, to be honest, since it is highly dependent on the application/game in question. For example, synthetic benchmarks often do not care about PCIe bandwidth, but some games are more sensitive to the reduction. It is also typically the case that the higher the resolution, the less the bandwidth matters (simply because the card needs more time to crunch the data, so there is less of a need to keep it constantly fed with more).

 

You can also check out this article at TechPowerUp. It uses a GTX980, but your scaling should be in the same ballpark. The result you are interested in is the "x4 1.1" row in the graphs, since that is the equivalent of a TB1 link. It shows a lot of results for specific games and also an averaged percentage of max performance at the summary page here.

 

Thanks so much. I decided to go the Thunderbolt route. But I can't seem to understand how to use the akitio with my notebook. And I thought TB1 is Pcie2x4 ?

[Yukikaze]

2 hours ago, Gogito said:

 

Thanks so much. I decided to go the Thunderbolt route. But I can't seem to understand how to use the akitio with my notebook. And I thought TB1 is Pcie2x4 ?

 

I suggest you look for people who have a GTX970 used with the Akitio. The guides section at the forums here should have what you need, since both the Akitio and the GTX970 are very popular for eGPU applications.

 

For a short version, you need:

1) Akitio Thunder2.

2) A Video Card.

3) If the card does not fit into the Akitio, you need to either make it fit, or you need a PCIe riser.

4) The means to power everything.

5) Thunderbolt Cable (in the case of the Akitio it is included).

 

As for bandwidth:

Thunderbolt 1 is equivalent to 4 lanes of PCIe Gen 1.

Thunderbolt 2 is equivalent to 4 lanes of PCIe Gen 2.

Thunderbolt 3 is equivalent to 4 lanes of PCIe Gen 3.