It looks like the rumor mill is starting back up regarding NVIDIA. It seems many believe that NVIDIA will be coming out with an 8GB variant of their flagship GeForce GTX 980 graphics card. This information comes from Hermitage Akihabara, who has been quite reliable in the past. This will of course boost Maxwell sales, but on top of that crush any 8GB card that AMD would be coming out with.
Running games at 1080p and even dual monitor setup the 4GB on the GTX 980 is sufficient. Now when you get into 4K gaming that 4 GB really started to get taxed. NVIDIA does get away with 4K gaming on the 4GB GTX 980 with great software and color compression techniques. You have to remember the card only has a 256-bit memory bus. Having double the memory would really help out in large resolution 4K gaming.
Not current single-GPU card can run modern 4K games at near-to-high settings. It is because these graphics cards do not have more than 4GB of memory. And for those running SLI or CrossFireX setups you should know that VRAM does not stack in those situations.
Having a single 8GB card would be ideal for people who want to game at 4K with high settings and who want a single card solution. Word is the card would arrive sometime in November. No word yet on pricing.