naturbo2000

As my sig. i5-2520M No external monitors hooked up. I connected my old main-rig monitor up to the eGPU once when I first set it up, but haven't since. My laptop is now my main rig (hence getting a Thinkpad) and use it either solo, or with the eGPU driving the (upgraded) internal LCD for gaming. Test above was via internal LCD if it matters.

365MB/s

I have a PE4L-EC200A (200cm), which works fine at PCIe 2.0. Any PCIe 1.x vs 2.0 issues seem to relate to connector impedance rather than cable length (at least up to 200cm). 200cm means I can use my laptop on the sofa :-)

I have a PE4L-EC200A (2m cable) which works fine at PCIe 2.0

I stand corrected. It is bplus site you linked to. I suspect the pe4l 2.1 is gen3 capable, but it's somewhat irrelevant as laptops seem to be reserving gen3 for thunderbolt.

But bplus doesn't say that it's gen2 capable (since nan do informed them). The link above is to Harmonic Inversion (a US distributor). And they obviously didn't get (or pay attention to) the memo that says it doesn't work. Edit: No You're Right, The Link Is To Bplus

The problem should not be the fact that it's a 100cm cable (I'm using Gen 2 on a 200cm cable on a T420). You say that you've tried going back to the PE4H and that was OK - have you tried the PE4H setup on your T530 (with bios set to Gen 1) or was that with your old T500? If the PE4H is working on your T530 but the PE4L is not, then I'd strongly suspect an issue with the PE4L. If you haven't tried the PE4H on your T530, you should do that next to determine whether it's a hardward issue with the PE4L or a software issue on the T530.

Not if you splice in HDMI connectors you can't. Your current score is gen 2, but adding connectors will cause signal reflections in the cable such that gen 2 stops working correctly (gen 1 is still OK). Higher quality connectors might help.

It will work. But you should check beforehand if gen 1 speeds are ok for you (via bios settings or setup.exe). I can't help but think a 780 will be horribly bandwidth limited. Please post your experiences of gen1 vs gen2 on your 780 if you go this route (preferably gameplay as well as raw benchmarks).

And if the goal is simply a longer cable and you haven't yet purchased it, I can confirm that the 2m variants work correctly at PCIe 2.0 speeds. If I recall correctly, even a single connector on the cable causes speeds to drop to PCIe 1.x due to signal reflections. FWIW there are connectors you could use for PCIe speeds, but they're phenomenally expensive: here

There's nothing wrong per-se with a 75cm cable length - I have a PE4L-EC200A which uses a soldered 2m cable. Works fine at PCIe 2.0. Of course 75cm + HDMI connectors might be too much (given the signal reflection issues caused by the connectors).

As promised - My 560ti448 egpu has watercooling and a mild overclock to 848MHz (max temp 46C running 3dmark11) 3DMark11 (which reckons on 5760 as the best/typical(?) graphics score for a 560ti448) External: P4973 (Graphics score 5513) Internal: P4875 (Graphics score 5383) This is in line with bjorm's much more complete tests in the previous message :-) NB - my external result is from a previous driver version. However I don't have a monitor handy to retest.

Cool - though given you're getting good results on your external monitor and the same results on your internal monitor (you mean internal result is the same as external, right?), then Optimus could only be working really really well rather than badly. If I get a chance to check my machine later I'll report back (T420 i5 and GTX560ti448). I'm guessing your machine has a 1366x768 internal display rather than 1600x900.

Not entirely true - his results look a lot higher than he'd get out of the iGPU. My expectation is that with a GTX560 he's simply not saturating a 1.2Opt link on the internal display. i.e. the bottleneck is the card rather then the PE4L. Edit: IMHO Getting sensible numbers for external use and being able to replicate those numbers when using the internal display is not a cause for complaint. i.e. you're getting 90% of desktop performance with an eGPU driving an external monitor. Great! And you're sad that the performance is not dropping off when you use the internal display? That makes no sense. So are you expecting to get 100% of desktop performance when using the card externally (i.e. a 10% gain)?

PE4H 2.4 can theoretically do a PCIe 1.1 x4 connection if you had 4ports on your laptop to connect to. (You'll be lucky to have 2). There is no point it having an x16 slot instead of an x4. PE4L (2.1) can do a PCIe 2.0 x1 connection (equivalent to a PCIe 1.1 x2). So it doesn't even need the x4 slot on its board... IIRC nvidia optimus only works with a x1 so unless you have a older laptop and need the extra ports of a PE4H, you should get a PE4L. The PE4H isn't worth more, but it does cost more probably due to the extra components.

My PE4L-EC200A arrived today (2m cable). Just wanted to mention that it behaves perfectly well at PCIe 2.0 speeds (tested with Heaven and a bunch of games). Obviously any issues with the non-captive cables are two do with signal reflections at the connectors - 2m of cable length has no problem with signal integrity.

About the closest example of what you might achieve is nando's own testing here: http://forum.techinferno.com/diy-e-gpu-projects/2904-12-1-hp-2530p-gtx560t-gtx460%40x1-opt-pe4h-2-4-a.html#post40076 You are going to be massively bandwidth constrained. Will there be enough bandwidth for 720p on modern dx11 games? Maybe just, but it will be mighty close. Dirt 2 isn't very demanding and only just gets almost 30fps at 1080p with high settings. I'd guess on a 660 being maybe 10% faster in your system (ti might be 20%) and there would be some gain from dropping to 720p, but I don't think that's enough for crysis 2 on high (I'm thinking more like 20-30fps on med!). Of course - this is speculation. I don't think we have data for anyone trying this, because it would be cheaper and better performance to use a lower spec graphics card with a higher spec laptop.

Absolutely - PCIe 3.0 is completely backwards compatible. The 660 will just work at PCIe 2.0 (x1) speeds. It's a real shame that the PE4H has an x16 slot as intuition tells you it _must_ be the one to get... it really isn't unless you can only run PCIe 1.1 (and want a detachable cable or to combine 2+ interfaces, like expresscard and mini-pcie)

GTX 570 is great - the only issue is that you're into diminishing returns (i.e. you're paying a chunk more cash for the card and won't see all the benefit of that cash). A GTX570 as a eGPU is better than a 560ti (or 560ti448), just not as much better as it is in a desktop system. If you can get one for a good price, go for it. That said - most of the 560/560ti/570 discussion comes from people doing this a while back. If the price it right, you should also consider 660/660ti which will work at least as well but with lower power requirements. My own choice of a 560ti448 was driven by the fact I could get it new from Amazon for £128 (below $200). I couldn't make a 660 or 570 make sense with their prices at the time. Check out Nando's main thread for 570 egpu benchmarks (including with an X220): http://forum.techinferno.com/diy-e-gpu-projects/2109-diy-egpu-experiences-%5Bversion-2-0%5D.html

My work T410 and my home T420 have "noisy" fans under load (as has every laptop I've ever used) - but at least they're both a fairly constant pitch (and nothing like the GTX560ti448 :-) ). It sounds like the T430 issue relates to oscillating pitch (because they ramp poorly between e.g. full-on and half-on). I'm guessing better software control would be enough to appease most users. I'm surprised Lenovo still haven't offered this.

I would expect that a T430 copes better with a quad core on the assumption that an ivy-bridge quad core is lower power (on sandy-bridge: the dual core is 35W and quad cores all 45W. On ivy-bridge, you can get a 35W quad core i7-3632QM). I had no issues with TOLUD. My T420 was a late model and already had a new enough BIOS for there to be no problem. It seems Lenovo have a habit of releasing TOLUD problematic BIOSes at launch and then fixing them up after enough complaints on their forums. All indications are that the problems are fixed in current Tx30 bioses, as long as you limit to 8GB RAM: https://forums.lenovo.com/t5/X-Series-ThinkPad-Laptops/X230-expresscard-adressing-eGPU/td-p/792909/page/3

I have a T420 as my main machine and throw the egpu in via the expresscard slot when I'm at a desk (for gaming driving a 21" monitor). Everything else (keyboard/mouse/sound) is plugged in by a single USB cable. So I think that matches your laptop-as-desktop criteria. I replaced an ageing Q6600 + 8800GTX setup with an i5 2520m + GTX560ti448 and am very happy with the result. Light enough laptop for using in the lounge but powerful enough for gaming when I want to (I'm currently looking at getting a PE4L-EC200A for gaming in the lounge ). Really cheap from the lenovo outlet (~600USD for the laptop plus other bits). It's possible to put a quad core in the T420, but everything I've read says the power and heat is too high (it throttles massively). A high spec dual core i5 seems to be the way to go in a 12-14" system. The 650 ti boost definitely looks to be the card to get right now. Close to 660 performance for a chunk less cash.