UPDATE (2/25/20): This article was written in 2007. We are leaving it intact for those looking for a historical perspective. If you are looking for the latest info about PCIe, check out our article about PCIe 4.0, which walks through the latest updates to the standard, including speed upgrades and a preview of PCIe 5.0.
PCI Express (PCIe) Mini Card slots have begun cropping up on Mini-ITX mainboards (learn more about Mini-ITX here) ever since the Santa Rosa platform made its debut. However, the PCIe Mini Card has been kicking around for quite some time, being used in custom-ordered laptops as wireless devices. Most of the documentation I have read about these cards dates back to 2005, which, in the technology industry, seems like a lifetime ago. So, why is it making its entrance into the Mini-ITX arena now?
What is the PCIe Mini Card?
The PCIe Mini Card is a replacement for the Mini PCI card found on many Mini-ITX mainboards. It is half the size of a Mini PCI card, measuring 30 mm x 51 mm. It has a 52-pin edge connector as opposed to the 100-pin stacking connector of Mini PCI Type I & II cards and the 124-pin edge connector of Mini PCI Type III. The new card is modeled after the Mini PCI Type III, but is sans side retaining clips.
The slot on a mainboard must support both an x1 PCI Express link and a USB 2.0 link because the PCIe Mini Card can utilize PCI Express and/or USB 2.0 connectivity. This PCIe Card has a 2.5Gb/s serial bus, providing a significant improvement in connectivity.
As I mentioned above, this card is not new news. So, why the introduction now? From what I can tell, it appears that it has something to do with getting the most from Windows Vista. Intel Turbo Memory (code-named Robson) is a flash memory add-on component for the PCIe Mini Card slot. Without having to become too technical here (which is certainly not one of my strengths), the Turbo Memory can perform two jobs (ReadyBoost and ReadyDrive—caching features of Windows Vista) in one small, internal package.
So, now that we have Mini-ITX mainboards boasting full Vista Premium support, it makes sense that these same boards also would provide PCIe Mini Card slots. There could very well be other reasons, as in the fact that Mini PCI is being phased out by the PCIe Mini Card standard; this is really due to PCIe replacing PCI.
Our ML350 industrial fanless computer also packs two PCIe Mini Card slots and one mSATA slot in a compact formfactor.
Mini PCIe cards & Industrial Computers
At OnLogic, we integrate Mini PCIe Cards to offer more configuration options & functionality. Thanks to mPCIe, we can enable CANbus, Wi-Fi, Bluetooth and 4G in many of our small form factor computers.
One of the main drawbacks for Industrial Computers & Mini PCIe cards are the limitations due to the motherboard adaptation to Mini PCIe cards. Luckily, there are brackets available that will convert your Mini PCIe card into a full-height card so you can adapt your system to bigger hardware needs. This way, more technology in your computer can be enabled regardless of the form-factor and motherboard layout.