I think that people do not realize that the Antenna of a Wireless card and its location is just as important (and in many cases even more) than the Wireless card per-se.
Consumers Wireless’ card chipsets come from five manufacturers and all hardware manufacturers get from them the chipset and basic drivers for their Wireless cards (Laptops and Desktops).
There can be day and night differences in the Wireless performance of Laptops that have the same Wireless cards. The One with better designed and placed Antenna will perform much better in term of coverage and bandwidth. As an example MacBook Pros Wireless tend to be better when Win 7 is used in Booth camp installation as compare to other Laptops.
Many other laptops use the same Wireless cards and Win 7 yet their performance is inferior because of careless design around the same card and software.
As for desktop, the main differences are in the Quality of the Antenna and its location.
Many PCI Wireless cards end up with little antennae stuck low behind the tower's metal back panel and the wall, thus the puny 33mW signal is grossly suppressed.
USB (I am talking about full size USB Module with an external Antenna not a silly Dongle/Nano) can be used with USB extension cord and put high above the system thus provides better propagation, or use a PCI card that it’s Antenna is extended via short coax.
Currently my choices are.
For USB -
http://www.newegg.com/Product/Produc...82E16833166046
For PCIe -
http://www.newegg.com/Product/Produc...82E16833106135
Both are Dual Band.
Some people ask, what about 802.11ac?
Right Now the overall demand for add-on 802.11aci s almost No existing, and the advantages are minuscule.
IMHO it does not worth while to get into quantity low price manufacturing of 802.11ac add-on Wireless cards.
However for people who suffer from the psychological condition known as “Early Adopter”.
One can try this -
http://www.newegg.com/Product/Produc...82E16833106192
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