External Desktop GPU for Laptop

• 

  Davo1111 on 13/02/2015 - 00:20

  +2

  The thing is, you need to have

  • a spare PCI slot
  • a compatible system
  • a spare graphics card
  • a spare power supply

  Once you add the graphics card, power supply, external gpu slot together, you're probably most of the way towards a shiny new computer anyway.

  EDIT: also appears to be version 2 PCI express, which is quite old http://en.wikipedia.org/wiki/PCI_Express#PCI_Express_2.0

  • 

    Arwedda on 13/02/2015 - 01:00

    isn't PCIe 2.0 x16 more than enough bandwidth for any graphics card on the market?

    • 

      Davo1111 on 13/02/2015 - 02:23

      This is from my research just now, so take it with a HUGE bucket of salt.

      • PCI version upgrades double bandwidth each time. So a PCI v1.0 is half the bandwitdth of PCI v2.0
      • Apparently a x16 slot will still work in 8x, but it will have half the amount of bandwidth
      • the cable plugging into the device is HDMI which has only 18 pins
      • PCI 1x ends at pin 17. So essentially the input from the laptop can only be PCI 1x

      So you've got a 16x graphics card, with a 1x output to the machine. imo that means the bandwith will be 1/16th of what it should be. That's assuming that the PCI version of the laptop is version 2.0, otherwise if it's 1, then that's half again.

      • 

        ProjectZero on 13/02/2015 - 10:20

        That's the gist of it, the bandwidth of the laptop will determine the bandwidth for the GPU…

  • 

    Manh on 13/02/2015 - 01:34

    Agreed and you've forgotten to include a spare monitor in your list. Also, they're asking for $70 for the gadget.

• 

  strangeloops66 on 13/02/2015 - 00:31

  Man, that looks like the guts of a Dalek spread across the desk! Cables everywhere.

• 

  airzone on 13/02/2015 - 10:50

  I've done this a few years back (using an expresscard adapter). It's also the basis for that external GPU thingie that Alienware have now (although their system has 4 lanes of PCIe, not a single one).

  There are huge gotcha's with this. Depending on your system resources, you will need to use some additional software (lookup "egpu setup 1.x") to disable PCIe ports (in particular any discrete GPU). Also, some laptop manufacturers whitelist devices to go into your PCIe ports, so nothing except the authorised wifi cards will ever work. Every laptop model is different.

  If you can get it to work, then you will need an nvidia optimus type of laptop to feed the video back to your laptop screen (with approx a 25% reduction in GPU performance due to bus bandwidth limitations), otherwise claim that performance back and use an external monitor.

  You will only have a single PCIe lane, so expect lower performance. My old system's lane capped out at 2.5ghz (which is PCIe 1.1 I think), so the card performed at about 33% of it's normal performance.

  If you get it all working, you will need to build a case to make it less ghetto. It's all fun, but I now have a laptop with a higher performing GPU in it.

• 

  scrimshaw on 13/02/2015 - 11:37

  Vidock
  http://www.villagetronic.com/g4/expansion-products/all

  Came out years ago. The idea was that it provided an enclosure with a built in switching power supply and all you needed was to throw in a GPU and that was it.

  The catch was you needed an external display and a Thunderbolt port on your machine, and most Windows laptops don't have one of these.