A comparison of the three current standards for laptops and notebooks
This is just a brief overview of the differences between the three major types of internal wireless (WLAN) adapters found in modern laptops. We won’t get into details like different chipsets or connection speeds, just the physical differences in form factor.
The oldest wireless capable laptops use Mini-PCI (Type IIIa), while laptops released after about 2005 use PCI Express Mini, also known as Mini-PCI Express or Mini-PCI-e. The newest laptops use the PCI Express Micro or sometimes called Half-Height PCI Express Mini.
How Old is Old?
Mini-PCI can be found on pretty much all laptops with built-in wireless networking made before 2005. Many computers that are now too outdated to have included built-in wireless at the time of purchase may still have a Mini-PCI slot, but this was used for 56K modem cards. Laptops produced after 2005 start to begin using PCI Express Mini. Today in 2012, arguably all new laptops make use of PCI Express Micro.
Show Me the Difference
It’s no surprise that the older cards are larger than the new ones. Below is an older Mini-PCI wireless adapter. It has 124 pin edge connection and an overall square shape. These cards are capable of 802.11g and 802.11b wireless LAN connection speeds.
Next we have pictured a newer PCI Express Mini card. It has a 54 pin edge connection and a rectangular shape. These cards support 802.11a/b/g/n wireless LAN connections.
And finally the PCI Express Micro (Half Height) which has a 52 pin edge connection and is roughly half the size of the PCI Express Mini card. These cards support 802.11a/b/g/n wireless LAN connections as well.
How Do I Know For Sure Which One I Need?
For starters, we’ve identified the correct type of card for thousands of laptop models within our database, so the easiest way is to browse parts for your laptop model by clicking your brand at the left. If we don’t have your model listed, you can look around the web for the answer, or do a visual check in your laptop.
Where Do I Install or Replace the Card?
We recommend first visually checking where your card is located, for several reasons. Most laptops have the card easily accessible from under a cover panel on the base of the laptop. However, there are a few models that require removing the keyboard or some disassembly to get at the card. Second, you should verify that wireless antenna cables are hooked up to your existing card, or are dangling near where the card belongs. Some older models were purchased without wireless networking capabilities would need new antenna cables to be retrofitted inside the computer.