AMD confirmed, amidst leaks last year that it will be looking to embed high-bandwidth memory (HBM) in an upcoming high-end GPU product.In a conference call with AMD’s CTO Joe Macri, he explained that HBM is primarily a form of extremely fast stacked chip tech which is going to be a game changer with GPU. AMD also mentioned subtly that main rivals are certainly green with envy since they are a year behind. So what’s HBM ? Since there’s a lot of intense pc tech jargon flying around, here’s putting it as close as simple as possible and that’s by addressing the main issues we currently have with graphic cards now, this is certainly important since this will allow you tap into the increased memory bandwidth therefore more performance.
Currently we’re at a point where the current memory, GDDR5 is now consuming a lot more power from the pc to perform effectively and looking at the bigger picture while GPU performance gets better with every passing year, GDDR5 starts draining the power heavily and it will eventually lead to memory bottlenecking. This of course means that GDDR5 would require a lot more space on the circuit board and the more performance boost means more chips and there’s only so many chips you can put in until you run out of space and suddenly you’re finding yourself having an inefficient GPU.
HBM, the future ?
In comes HBM, stacked memory has been around but AMD has implemented it in a neat way. Instead of spreading it around the GPU, HBM vertically stacks it on top of each other using TSV’s (Through-Silicon Vias). Since GDDR5’s ram chips have to travel longer to the GPU means there’s more power. HBM does this by going vertical like a skyscraper arrangement allowing wire length to greatly reduce. This is possible by allowing the wires to go through holes in the stack. Visualize it in way a string goes through dominoes. So the wires don’t have to travel, means less power and now even lesser build space required for GPUs. AMD, by designing the “Interposer” allowed it to sit between the gpu and HBM DRAM allowing it to connect it to GPU as close as possible that achieves the performance bump by a big margin. 
So here’s what this design will change, it will up performance, reduce power consumption and you find yourself having a massive upgrade from GDDR5 pumping higher performance but running on lower clock speeds. HBM operates at a lower voltage too, more significantly you will have a card that won’t require a lot of space that makes the scope for building a more compact yet powerful PC build.
I’m a Gamer, why should I care ?
We will see HBM releasing on what Joe Macri termed “High-end GPUs” which indicates that we will see this tech go on retail with the Radeon 29 390X and future AMD GPU’s. It’s going to be interesting to see what HBM has to offer since rivals Nvidia will have to content with AMD with the GTX 980 Ti which may end up having greater memory capacity but not so much so with the bandwidth edge the R9 could have with HBM. HBM sounds like the future of VRAM, although it looks good on paper and numbers have it for them, AMD hasn’t revealed anything more that is reflective of their performance so we’ll have to wait for benchmarks in the coming months. However it does mean that AMD users will suddenly see radically different designs and recently EA technical director Johan Andersson tweeted AMD’s upcoming flagship.
This new island is one seriously impressive and sweet GPU. wow & thanks @AMDRadeon ! They will be put to good use 🙂 pic.twitter.com/S5hyD6vxNh
— Johan Andersson (@repi) May 22, 2015
Keep in mind that Johan Andersson is one of the minds behind EA’s Frostbite, so could we see future games powered by AMD’s Vulkan. More so the picture confirms leaks about what the Radeon 390X takes cues from the R9 295x and while it hasn’t been official from AMD yet it appears it will have integrated water cooling evident from the lack of fans in the GPU.
Earlier leaked renders showed the 390X to have a short length and Andersson’s image confirms this, more so the GPU looks ever shorter than standard bulk high end cards which means that HBM stacking RAM on top has reduced their footprint.The 390X is rumoured to be powered by a Fiji GPU and AMD has promised to reveal more at Computex by June end and we could see a PC gaming dedicated event at E3 gaming expo next month which AMD is hosting.
