Mobile PCI Express Module (MXM) is an interconnect standard for GPUs (MXM Graphics Modules) in laptops using PCI Express created by MXM-SIG. The goal was to create a non-proprietary, industry standard socket, so one could easily upgrade the graphics processor in a laptop, without having to buy a whole new system or relying on proprietary vendor upgrades.
Generations
Smaller graphics modules can be inserted into larger slots, but type I and II heatsinks will not fit type III and above or vice versa.
Dell's Alienware m5700 platform uses a heatsink that will fit Type I, II, & III cards without modification.
MXM 3.1 was released in March 2012 and added PCIe 3.0 support.
First generation modules are not compatible with second generation (MXM 3) modules and vice versa. First generation modules I to IV are fully backwards compatible.
*Deprecated/abandoned, became/replaced by MXM-III (HE)
*Some MXM cards have different mounting screw hole configurations, always check the mounting holes of the MXM card and verify that they match those of the card you plan to upgrade to.
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