Tuesday, November 12th 2013
AMD Announces the Radeon R9 270 Graphics Card
AMD announced a new SKU to heat up the sub-$200 market segment, the Radeon R9 270. A slightly tuned down sibling of the Radeon R9 270X, the R9 270 is based on the 28 nm "Curacao" silicon, and features a similar core-configuration to it. The chip features the same 1,280 stream processor-count as the R9 270X, with 80 TMUs, 32 ROPs, and a 256-bit wide GDDR5 memory interface, holding 2 GB of memory, but features lower clock speeds, at 900 to 925 MHz core (PowerTune with Boost), and 5.60 GHz memory (GDDR5-effective), which churns out 179 GB/s of memory bandwidth. Its TDP is rated at 170W, and the card draws power from a pair of 6-pin PCIe power connectors. The GPU supports the latest APIs, including DirectX 11.2, OpenGL 4.3, and Mantle. The card starts at $179.99.
14 Comments on AMD Announces the Radeon R9 270 Graphics Card
It sure seemed to me that 7870 was binned to hit 1200mhz+ at default voltage (1.21v). Going by my old adage of 56.25gbps/TF, assuming you could hit 5400mhz or so on the ram (meaning if you got a card with hynix ram or by luck non-crappy elpida chips) you're fine for ~20% more performance.
While the change to 6ghz ram certainly adds a few percent performance at the same core clock, the binning changed on 270x to the point you may lose that performance gained by clockspeed overclocking (they are not binned to 1200mhz). In essence the bottlenecked shifted from the ram to the CUs. Makes sense...faster ram got cheaper and allows amd to sell a lesser chip (total BOM) at the same price.
280x and 270/x are a strange breed. AMD seemed to stop giving a crap about chips are not fully functional, opting instead to bin them to lower clockspeed/more variable leakage/power consumption to keep cost down and then rounding out the variation of chips (and separate their stack) with powertune limits.
It is truly strange days.
270x is probably greater than 7870, if barely, on average (with more power consumption)...but I highly doubt the same is true of 270 vs 7870 as the faster ram and crappier chip binning will hit the same or lower powertune limit in a less optimal fashion.
It can be inferred the top allowed aib model for 270 is 975/5.6. That will perform exactly the same as...you guessed it...7870 at 1000/4800 (doubling of ram bandwidth over what is required gives ~16% performance...the math comes out to the same thing as 7870 at 1001/4800 if exactly 16%). The chip will likely have similar or higher voltage and higher power consumption as a stock 7870 at those clocks. Since 6ghz ram will also ramp up power consumption over 4800, while giving less performance improvement than using that same power use for core clockspeed, especially at the edge of powertune limits, then odds are it will be an inferior but cheaper combination for an overclocker. Say it hits 1100/~6400 in 170w...that would place it proportionally lower to a typical 7870 as 7870 is to 270x. Not a huge chunk, but separation non-the-less constituting that $20 or so between products.
It's probably just evolution based on conditions (ram prices and the evolution of the 28nm process) and reusing of chips with a more lucrative criteria. No different than 670/660ti vs 760 fundamentally, but a different method.
AMD will hold the 270X resolute at $200, but these by after Christmas might be $150-160 and/or might have a copy of BF4 with them. Kid's with money and hearing how Mantle runs BF4 with older- mainstream boxes might see this route more of a boon against the newer console as the option to get to play.