This is what I'd do in your situation. I'd instead pick up an XFX R9 Fury X which is currently going for $308 on Amazon, which is currently still the most powerful singular GPU solution from AMD and only about $50 more than an RX 480 8GB. Then since it will likely retain a fair amount of its value, I'd consider reselling it after the Vega launch, recuperate the funds and then make the Vega purchase if you so desired. This way, you'll already have the most powerful AMD hardware available and you can rest easy while making a decision about upgrading to Vega once it launches without feeling desperate for extra performance.
At your resolution, the R9 Fury X is more than sufficient for the games you intend on playing (AAA) and will most definitely provide the highest quality experience for the time being. The RX 480 simply doesn't cut it in regards to enabling Ultra settings while maintaining a guaranteed 60+ FPS in all titles and if that statement holds true today, just think about a year or more from now. It's a fantastic GPU for those looking to upgrade to simply meet the standards, but not to exceed them.
Considering the RX 480's floating point performance is roughly 5 Teraflops and the R9 Fury X is roughly 9 Teraflops, the choice is clear which GPU is better suited for high end gaming experiences. Here's a comparative benchmark of their performance and the RX 480 simply isn't even close to residing in the same league as the R9 Fury X. So, to guarantee that you're satisfied with your purchase, you'd very much so be better off buying the R9 Fury X, not only currently, but when considering that its value won't depreciate as much as the RX 480's will if you ever intend on reselling it down the line when ready to upgrade to Vega.
At your current resolution, if you purchase an R9 Fury X you'll likely be satisfied with your performance enough to forego purchasing Vega at launch and watch the price stabilize/decrease before committing to the upgrade or possibly even have enough performance to await Vega's successor Navi and there's no way that an RX 480 purchase would put you in that same position of consumer peace of mind.
There's even a rebate being offered which brings the price down to $288, so just food for though. For an extra $38 over the price of an RX 480 8GB, you're getting an extra 4 Teraflops of floating point performance. Now that's what I call a price to performance ratio!
Ok i have a few questions.
Will 4GB be a limit at all because i know with forza on my current GPU that has 2gb of vram, and the game is hitting 4.5GB of vram usage on low settings at 1200p res.
Also do you know if it would come with displayport adapters? Because i run 3 monitors and one of them does not have displayport or HDMI,only DVI and VGA.
Good question. So, here's how one should always tackle the question about Vram limitations or lack thereof. At your resolution of 1920x1200 4GB of Vram will be sufficient for Ultra settings in triple A titles for the foreseeable future, pending you're not going to install insane amounts of mods on a game such as Fallout 4 (As an example).
Yet, let's consider it as if it's a fact and you are indeed planning on playing Fallout 4 with a massive amount of mods on it, but instead using an Rx 480 8GB filling the entire 8GB of Vram. What you'll run into is the issue that an RX 480 Polaris 10 based GPU simply isn't capable of handling such massive amounts of data at a quality level that would be deemed acceptable (45 FPS+). If the entirety of the RX 480's 8GB of Vram was filled, it would simply be starving for resources to be able to render what it's being given and thus making 8GB on a Polaris 10 redundant. Instead of the aformention acceptable standard of say 45FPS, the RX 480 8GB would be operating Fallout 4 with 8GB of mods at sub 20 FPS.
So with that being said, it's simply a marketing ploy, because bigger means better to the general consumer. When looking at the 4GB and 8GB versions of the RX 480, it's easily seen that the RX 480 simply doesn't benefit from the extra Vram resources, because the Polaris 10 GPU itself simply cannot handle it at respectable rendering resolutions.
Now pending you are simply going to operate as an example DOOM, Battlefield 1, Fallout 4 or The Witcher 3 at 1920x1200 on Ultra settings (Vanilla/no mods), you wouldn't utilize more than 3.902 GB of Vram at a exaggerated maximum anyways and with that being said, what would be most important is the rendering power of the GPU itself to produce as many frames as possible utilizing the aforementioned settings, which the R9 Fury X would absolutely out class the RX 480 in every game by not just a few frames, but absolutely destroy it in comparison.
Here's a fairly accurate comparison of the RX 480 and the R9 Fury X benchmarking both across multiple titles using Ultra or higher settings across multiple resolutions. As you can see, the Fury X isn't starved for Vram, but the RX 480 is definitely staved for rendering resources in comparison. With that being said, if you had to choose between the two cards, the choice is clear, especially the slight price difference between them both at the moment.
Now in regards to a Display Port-DVI adapter being included, I don't believe that one is, but they can easily be found for fairly cheap, so I wouldn't let that be a deciding factor during the decision process. Below I have posted some helpful information in regards to the R9 Fury X that you might deem useful. If you have any more questions, feel free to ask and I'll assist you in determining if the R9 Fury X or anything else is currently an acceptable upgrade for you at 1920x1200 both now and in the future instead of awaiting the Vega 10 GPU (Which is still obviously an option, but might possibly be a ways off and may exceed your budget, but no one knows the pricing details as of yet). Patience is a virtue, but when it comes to cutting edge components still comes at a premium price.
R9 FURY x GPU ARCHITECTURE 28nm API SUPPORT6,7,8 DirectX® 12, Mantle, OpenGL® 4.58, Vulkan™, OpenCL™ 2.0 HIGH-BANDWIDTH MEMORY1 (HBM) Yes PCI EXPRESS® VERSION17 3.0 Virtual Super resolution (VSR)4 Yes AMD FreeSync™ technology5 Yes AMD liquidVR™ technology9 Yes 4K RESOLUTION SUPPORT3 Yes FRAME RATE TARGET CONTROL (FRTC)11 Yes DDMA AUDIO Yes HDMI (WITH 4K, STEREO 3D, DEEP COLOR & X.V.COLOR™) Yes AMD POWERTUNE TECHNOLOGY13 Yes AMD ZeroCore Power Technology13 Yes AMD TRUEAUDIO TECHNOLOGY15 Yes AMD EYEFINITY TECHNOLOGY10 (MAXIMUM DISPLAYS) Up to 6 displays with DisplayPort MST hub AMD HD3D Technology18 Yes VIDEO CODEC ENGINE (VCE) (WITH H.264, MPEG-4 ASP, MPEG-2, VC-1 & BLU-RAY 3D) Yes GPU CLOCK SPEED Up to 1050 MHz MEMORY BANDWIDTH 512 GB/s MEMORY INTERFACE 4096-bit HBM MEMORY AMOUNT 4GB HBM STREAM PROCESSING UNITS 4096 (64 Compute Units)19 REQUIRED POWER SUPPLY CONNECTORS 2x 8-pin AMD CROSSFIRE™ SUPPORT12 (MAXIMUM NUMBER OF GPUS AND CROSSFIRE BRIDGE INTERCONNECT REQUIRED) 4, no FORM FACTOR Full height, dual slot, liquid-cooled
Something to keep in mind, when new high end video cards are released, availability is low at the beginning, and recent trends have them charging over MSRP due to scalpers unless you get lucky enough to buy in time from newegg or amazon when stock is available. There's also the rough drivers to put up with at release. So you might not be able to buy the new vega cards for 1-4 months after release depending on how good the card is. I am talking about the high end vega. You might even have to wait for the lower end follow up cards.