Just to let you know. There is 2 problems with the gtx900 series. One is the last 500 MB of the 4GB version used to swap or something and that is not additionnal GPU memory to use with a 4K monitor for example. The model Gtx980 and + use full 4GB. The AMD cards if they are 4GB use 4GB but they are most of the time 3GB models.
http://www.pcworld.com/article/28757...-in-specs.html
Another problem is the coil whine (know as electronic buzzing noise) Mostly on GTX 970 and 980.
I got this problem with my fresh new GTX970 I need to return
The worst is that you can have an audio card like a soundblaster with a cheap preamp in it and you not gonna hear the problem at all but if you switch to a better audio card with a nice powerful pre-amp be prepared for the noise attack. LOL
http://www.pcper.com/news/Graphics-C...Whine-Concerns
http://www.hardwarecanucks.com/forum...stigation.html