My graphic card has gotten very loud. What cooling would you recommend?

Do you really mean it only got loud recently? That would probably indicate some problem with the heatsink assembly.
Unless you've attached another card in the adjacent slot - I'm quite sure this has a drastic effect on cooling performance/noise for this particular card (and I'm forced to that setup, unfortunately...).
I also found the fan settings too aggressive, and used radeon bios editor to correct this - decrease minimum fan duty cycle, and increase the min temperature (previously the card stabilized at around 65 degrees and made a lot of noise - now it's more like 75 degrees but noise is much better, this should still be a safe temperature). Though using windows you can probably use CCC for adjusting fan speed and don't need RBE.

A simple solution to your problem is this: remove the cooler cover,unscrew the card fan and replace it with a 80mm nexus real silent.All you need is a thin screwdriver and 4 screws that will match.I've done it and now it's both inaudible and cooler.The nexus fan is connected to the motherboard and is controlled by the mobo bios~900rpm.......silance at last.Hope that this will help you.