I want to start this thread to collect information on where to obtain the latest AMD GPU's on MXM cards.
I have since the creation of this article now owned the Clevo Radeon HD 7970M 2GB, Clevo Radeon R9 M290X 4GB and now I own the Dell Radeon WX7100 8GB MXM GPU.
My first MXM laptop has been the Clevo P150EM and then I switched over to an Alienware M17x R4 which supports the 3rd generation Intel GPU but this allowed me to use WX7100.
Remember that workstation cards can accept mainstream vBIOS, W7170M can be flashed to M390X and WX7100 to either Rx 480 or Rx 580 because they are the same cards but better binned generally (higher quality).
2011 - Radeon HD 6990M 2GB (40nm) 100W MXM 3.0b (These work in virtually any laptop with MXM port)
2012 - Radeon HD 7970M 2GB (28nm) 100W MXM 3.0b (These work in virtually any laptop with MXM port)
2013 - Radeon HD 8970M/R9 M290X 2GB/4GB (28nm) 100W MXM 3.0b (These cards work in virtually any laptop with MXM port)
2014 - Radeon R9 M295X 4GB (28nm) 100W MXM 3.0b (Hard to get hands on, same performance as M390X)
2014.08.25 AMD FirePro W5170M 2/4GB (28nm) MXM 3.0a
2015.10.02 - AMD FirePro W7170M/Radeon R9 M390X 4GB (28nm) 100W MXM 3.0b (Confirmed to work with MSI, HP & Dell laptops)
2016 - Embedded Radeon E9260 & E9550 (14nm) Polaris MXM 3.0a & 3.0b (Extremely expensive, avoid)
2017 - Radeon Rx 480 4GB/8GB (14nm) Polaris 100W/150W MXM 3.0b (Warning! Does not work with Clevo!)
Eurocom.com sells brand new Rx 480 100W TDP MXM, ask their support for details.
2017 - Radeon Rx 560 4GB (14nm) Polaris 55W MXM 3.0a (Does not work with Clevo!)
2017 - Radeon Rx 580 4GB/8GB (14nm) Polaris 100W/150W MXM 3.0b (Does not work with Clevo!)
Eurocom.com sells brand new Rx 580 150W TDP MXM, ask their support for details.
2018 - Radeon PRO WX 4130 2GB (14nm) Polaris MXM 3.0a
2018 - Radeon PRO WX 4150 4GB (14nm) Polaris MXM 3.0a
2018 - Radeon PRO WX7100 8GB (14nm) Polaris 100W MXM 3.0b (Confirmed working in MSI and Dell laptops)
If you know any other cards or places to get these MXM discrete GPU's, please add them in the comments below, MXM cards are getting harder and harder to obtain these days and it looks like the only places to get the latest are sadly the embedded market which I have no idea how to access.
If you want to buy GPU's through Taobao do so through third party agent websites that buys the items for you and ships them to you, Google it there too many for me to list I can recommend Bhiner but there may be better ones.
Useful forums for MXM users:
2017.03.26 - Added Radeon Rx 480 MXM from TaoBao and updated some links
2018.05.06 - Added Radeon WX 7100 MXM GPU, added more links removed and corrected some links, added illustrations and included the first generations of GCN cards because they are still relevant today.
2019.05.09 - Added more mid range cards to list and added link to getting Polaris cards working with eDP and 120Hz displays.