I'm looking for a possibility to make my desktop WiFi compatible. Currently I'm using a USB-stick that connects to the router, but it's not the best solution as it sometimes loses connection and isn't made for continuous service. Thus I started looking and found that PCI cards have better performance. My current pricing wish would be around 30, but it wouldn't be a big deal if it cost more. My Mainboard is an ASRock Z77 pro4 and the only PCI slot I'm using is for my graphics card (This graphics card blocks the neighboring PCI slot).I want to sometimes play online with the card, so connection quality should be as good as possible and several hours of operation should be no problem. I'm using Win7 and (arch)Linux. Note that I'm not up to date on the PCI standard, so I use PCI to refer to PCI-e, 2.0 and 3.0 interchangeably.
PCI(e?) WiFi card
gaming;network adapter
I recommend the TP-LINK TL-WDN4800This card uses PCI-E. According to your board specs, you have a slot for this. You do mention your card blocks the neighboring slot - you will need to check that though, as the PCI-E slot is next to one of the slots you'd put a video card in. Other features include:Dual band (it operates on both the 2.4GHz and 5GHz bands). You should be able to connect to almost any wireless network.Compatible with wireless networks that use the B/G/N(2.4Ghz) and A/N(5GHz) protocolsThe biggest down side is that it is slightly above your budget at $40 (which Google tells me is currently 35.50). As a side note, if you are willing to spend more, there is a new version of this card available too. It is the TP-LINK Archer T6E AC1300. The major difference is that this also supports the newer AC protocol. 