Twice the fun ...
So a year and a half ago ATI released the Radeon HD 4870 X2 - to date one of the most canny dual-GPU solutions available on the market. It still is a hefty beast of a graphic card really, but it surely will be outclassed by the new Radeon HD 5970. But what exactly is the Radeon 5970 some of you might wonder ?
RV870 + RV870 = R800
The above math is the reality. Though the X2 extension has been stripped away, a Radeon HD 5970 graphics card really is a what you learned as Radeon HD 5870 X2 e.g. two RV870 + RV870 mounted on one PCB.
The RV870 GPU -- First let's focus on the sheer technical specifications per GPU. Transistor count for example. The number of transistors always works as an indicator of how powerful a product will be. For example, the Radeon HD 4870 which we all know and love for its performance had 956 million transistors embedded onto that die. The RV870 GPUs have 2.15 billion transistors. Correct, that is 2150 million transistors tucked away in a small chip the size of the tip of you finger.
Each RV870 GPU on the Radeon HD 5970 will have the full 1600 shader processors available (also called stream processors). The number of ROPs went up from last gen's 16 to 32 and the texture count is 80. So one GPU is already staggering when it comes to performance -- you now have two.
When ATI launched the RV870 chip (Radeon HD 5870), AMD effectively again doubled up performance over the last-gen product (Radeon HD 4870). Quite an achievement. So as you guys know the Radeon HD 5870 is an amazing product already.
The Radeon HD 5970 -- What ATI did with the Radeon HD 5970 is to place two RV870 chips onto one PCB. In-between the two chips there's a bridge chip (PLX) allowing direct communication in-between them. So while this card is marketed as a 'single' graphics card. The reality however is that the two GPUs are bridged and then kicked-in into Crossfire mode -- Multi GPU gaming. The 5970 is also marketed as 2GB model -- well, to date two GPUs can't share a framebuffer, so the reality here is that each RV870 GPU has a 1GB memory partition.
| Radeon HD 4870 | Radeon HD 5850 | Radeon HD 5870 | Radeon HD 5970 | |
| Process | 55nm | 40nm | 40nm | 40nm |
| Transistors | 956M | 2.15B | 2.15B | 4.3B |
| Die Size | 263 mm² | 334 mm² | 334 mm² | 334 mm² |
| Core Clock | 750 MHz | 725 MHz | 850 MHz | 725 MHz |
| Shader Processors | 800 | 1440 | 1600 | 3200 |
| Compute Performance | 1.2 TFLOPs | 2.09 TFLOPs | 2.72 TFLOPs | 4.64 TFLOPs |
| Texture Units | 40 | 72 | 80 | 160 |
| Texture Fillrate | 30.0 GTexels/s | 52.2 GTexels/s | 68.0 GTexels/s | 116.0 GTexels/s |
| ROPs | 16 | 32 | 32 | 64 |
| Pixel Fillrate | 12.0 GPixels/s | 23.2 GPixels/s | 27.2 GPixels/s | 64.4 GPixels/s |
| Z/Stencil | 48.0 GSamples/s | 92.8 GSamples/s | 108.8 GSamples/s | 185.6 GSamples/s |
| Memory Type | GDDR5 | GDDR5 | GDDR5 | GDDR5 |
| Memory Clock | 900 MHz | 1000 MHz | 1200 MHz | 1000 MHz |
| Memory Data Rate | 3.6 Gbps | 4.0 Gbps | 4.8 Gbps | 4.0 Gbps |
| Memory Bandwidth | 115.2 GB/s | 128.0 GB/s | 153.6GB/s | 256.0 GB/s |
| Maximum Board Power (TDP) | 160W | 170W | 188W | 294W |
| Idle Board Power | 90W | 27W | 27W | 42W |
You can imagine that powering up a graphics card with so much brute horsepower also would double up on power consumption, and that's where ATI made the call to clock this product a little slower than the Radeon HD 5870.
The Radeon 5970 will get a clock frequency at 725 MHz with it's total of 3200 (!) stream/shader processors. The memory is clocked at 4000 MHz effective(gDDR5). The end result of this is a graphics card with an idle wattage of 42W (less then your average dedicated graphics card anno 2009) and the peak wattage (two GPU 100% stressed) is then 294 Watt. And sure that's a whole lot alright but considering what we are dealing with, not exactly surprising or concerning. So while we have the full Radeon HD 5870 spec available including the 1600 shader processor, it's clocked (per GPU) at Radeon 5850 specification.
Here's the kicker though, the 5970 cards will come 'unlocked' as ATI likes to call it. That means full control on overclocking. So if you want to forfeit on power consumption and can move beyond 300W, you could take this card to 800 ~ 900 MHz perhaps even 1000 MHz yourself and gain even more performance out of it -- at the expense of higher power consumption though.
Memory wise it's exactly the same dynamic as ATI will be equipping the cards with gDDR5 memory rated at 5000 MHz.. We also expect board partners to release Limited Editions and overclocked models really, the card oozes with tweaking potential. Voltage regulation will also be an integral part of that as the card comes with multiple programmable Volterra power regulators.
Now many of you are still happily gaming with it, so I threw it into the table above .. but check that out -- the 5970 (in performance) is specced nearly 4x times faster than a Radeon HD 4870. And then we are leaving out the features like the new UVD 2.0 engine, Eyefinity and hey the card being a full DirectX 11 class graphics with hardware tessellation unit.
Yes the Radeon HD 5970 is a true gamers or enthusiast PC aficionado's wet dream.
It's going to be difficult to justify this product though, as such incredible brute horsepower requires a massive PC and the most complex games to even stress the GPUs 100%, a challenge yes -- but I like to refer to that as purchasing a future proof graphics card.
