Just make sure that the chipsets are compatible (same as on cards people had good results with) and you will be fine. You and mr-andrek do not have the same machine generation so not the same rules/limitations apply.I have to ask again because I read that the HP 4540s isn't whitelist-limited.
So can I use also not HP branded AR5B195's without problems for WIFI & Bluetooth (also under Windows)? Or is it better to go with HP branded ones?
I can't give you any guarantees, but that probably is written there because the whitelisting was used for quite some time and drooped (to the surprise of many) only in the latest generation and the ebay sellers are rather safe then sorry, since the most people upgrading wifi cards have older generations of notebooks.I have found this one in Europe: http://www.ebay.de/itm/Atheros-AR5B...Computing_NetworkCards_RL&hash=item43bc2dff05
But the description says: "Can't use on IBM & HP due to BIOS whitelist"
So this is why I ask. The chipset ist a AR9285 for WIFI and AR3011 for Bluetooth - so it should work (in case that whitelist problems do not apply)?