AMD Fiji Die Reconstructed - 4 HBMs And A Huge GPU Uncovered

A Fiji die reconstruction has been achieved past stitching together multiple images published by AMD showing diverse parts of the dice. What has been uncovered is very interesting and matches the retentivity spec that our sources take been telling us about.

A Fiji Graphics Card As Shown On Twitter By Johann Andersson And AMD

At present I should indicate out that nosotros have been working on our ain analysis and calculations effectually the Fiji dice for a few days. And we'll be referring to our ain numbers, yet we'll employ Videocardz'south visual reconstruction for illustrative purposes.

AMD Fiji Dice Reconstructed - 4 HBMs And A Huge GPU Uncovered

Now the first thing you'll find is that there are iv HBM stacks packed on the same interposer every bit Republic of the fiji islands. Just as AMD'due south Joe Macri had unsaid a few days ago. Each HBM stack has a capacity of 1GB of memory, as far as we are aware stacks with more capacity are non bachelor even so. The second affair y'all'll notice is that Republic of the fiji islands is actually quite large. The largest GPU AMD has always engineered in fact.

AMD-Fiji-Graphics-Processors With regards to measurements, the GPU is exactly 21mm wides. We arrived at this by using the width of an HBM module equally a measuring stick. Because we know an HBM stack is exactly 5mm broad. We went through AMD'due south official rendering and measured the width pixel by pixel. And we arrived at exactly 21mm.
AMD HBM Fiji The acme is where it gets tricky however. Nosotros know for a fact that Fiji is at least 26mm long, this is over again by using HBM's length, which we know to be 7mm, every bit a measuring stick.
And so finally, we go far at GPU die size range of 546mm² to 588mm² based on a fixed width of 21mm and possible lengths ranging from 26mm to 28mm. Nosotros'll have the average at 567mm² giving us a ~4% deviation range, which is actually quite decent.

At present the question is, with the area savings enabled by the significantly smaller HBM retentivity interface compared to GDDR5, does this let AMD to cram 4096 GCN stream processors into a 567mm² die ? Stay tuned for the answer in an article coming shortly...

Let's briefly discuss Fijis new secret weapon, HBM.
HBM represents the revolutionary step that has been so badly needed in the evolution of graphics memory standards. The starting time generation of HBM promises to deliver 4.5X the bandwidth of GDDR5 and a staggering xvi times the bandwidth of DDR3.

Hynix-HBM-15 Both GDDR5 and DDR3 are eclipsed by the 128 GB/s figure for first generation HBM.
The second generation promises to double the bandwidth by doubling the speed from 1Gbps to 2Gbps. While also quadrupling the retentivity chapters for four-Hi stacks from 1GB to 4GB. HBM2 will be featured in AMD's upcoming Arctic Islands graphics architecture with the "Greenland" flagship GPU.

AMD GCN HBM High Bandwidth Memory

In our technical deep dive on Republic of the fiji islands nosotros were able to draw a rough approximate of the Republic of the fiji islands'southward performance based on the core count and the GPU clock speed. But as nosotros tin can't yet quantify the performance benefit from HBM without rigorous testing nosotros left information technology out of the equation. Even without putting HBM into the equation the estimated performance of Fiji XT is quite phenomenal

Below are the unconfirmed/unofficial specifications for Fiji based on the R9 390X WCE rumor ( except for memory chapters ). and the SiSoft Sandra database leak.

WCCFTech	AMD Republic of the fiji islands Flagship	AMD Radeon R9 290X
GPU Code Proper name	Fiji XT	Hawaii XT
GPU Cores / Shaders	4096	2816
Memory	4GB Stacked HBM	4GB GDDR5
Memory Frequency	1.00Ghz	5.0Ghz
Retentiveness Interface	4096 Wide IO	512bit GDDR5
Full Memory Bandwidth	512GB/South	320GB/S
GPU Clock Speed	ane.05Ghz	1Ghz
Compute Functioning	8.5TFLOPS*	v.6TFLOPS
Launch Cost	$649	$549