I put intel 6235 wifi cards in my laptops. They work good on any home router. But when at work on a zone director 3000 and 7982's i have to turn both 2.4GHz and 5ghz to 20MHz only and not to auto, and it is still tricky to get them to connect. I do not get the full benefit of dual band wireless. The driver is updated on the card. And i am running the latest firmware on the 3000. I also am running channelfly if that makes a difference and the channels are optimized for compatibility.
Added is a pic from the config of the laptop.
HP Elitebook 9470m has the same Intel 6235 wifi card. We have multiple 7982 AP's. Usually the wifi card connects fine, but there are problems especially when roaming from AP to another. The wifi card must be disabled and enabled to connect to any wlan again. I've been updating to the latest HP issued drivers and then to the latest Intel issued drivers dated 14 Nov 2013. I have also disabled all the power saving features related to the wifi card. I'm about to create a support ticket with HP.