I ordered this cooler as the stock cooler on my ASUS Radeon HD 4850 became next to useless after a while, since it was simply recirculating warm air. The fact that this cooler draws air from inside the case over its heatsink and then exhausts it out of rear of the PC means that this should no longer occur.
The cooler requires that you remove the graphics card from your PC, if it is already installed and remove the existing cooler. My stock cooler was attached with 4 small spring loaded screws, which required a small screwdriver (about half the size as a phillips head).
It is recommended that all traces of old thermal compound are removed using a special solvent, although to be honest I managed fine with just a lint free cloth. Better cooling performance would probably be achieved with a more maticulous approach however.
The supplied thermal paste is nothing special, enthusiasts would definitely prefer to use some premium thermal compound, but again I didn't bother since I was only hoping to solve the issue of recirculated air inside my case.
It's very easy to attach the Vortexx cooler, simply apply thermal paste to the GPU die and bring the cooler into contact with the graphics card. The cable which supplies the fan power is designed to connect where the stock fan used to, however the design was different to my ASUS Radeon HD 4850, so I had to use the adapter and connect straight to one of my power supplies molex connectors.
Compared to the stock cooler, my graphics card and case temperatures are considerably cooler - motherboard chipset temperatures are around 20'c less and the graphics card no longer overheats and crashes, like it used to when used for more than a few minutes with a demanding 3D application. The Vortexx cooler is also very quiet, despite running at full speed due to being connected straight to my PSU.
Overall a very good value for money solution for anybody hoping to improve on their existing GPU cooling quickly and easily.