With the series having already exploded onto the market this twelvemonth, a new Radeon 200 graphics carte du jour may not make for the about exciting headline, but this ane is a little different than almost other Radeon 200s because it isn't a rebadged Hard disk drive 7000. Codenamed "Tonga Pro", the new Radeon R9 285 takes the latest engineering science from the R9 290 range and makes it more affordable.

Equally a mid-range GPU, the R9 285 is meant to evangelize mainstream performance at a competitive price. The "Tonga" GPU is essentially a newer, cheaper to produce version of the tried and true "Tahiti" GPU that has been used by many cards. For the R9 285, Tonga has been configured similar to the way Tahiti was for the Hard disk drive 7950, which is the same as the R9 280's configuration.

This new GPU is based on the latest incarnation of the GCN (Graphics Core Side by side) architecture and supports DirectX 12 capabilities, Eyefinity, TrueAudio, Project FreeSync, next-gen Crossfire engineering science, next-gen PowerTune technology and 4K H.264 decode back up. Yet, information technology does have an inferior retentivity controller to Tahiti, which is what makes it cheaper to produce.

The R9 280 debuted with an MSRP of $249 and this is the exact price point that the R9 285 is arriving at, placing it direct between the R9 270X ($200) and R9 280X ($300). Given their like names, specifications and pricing, it's not surprising therefore that the R9 285 is replacing the R9 280, leaving the latter with a relatively brusque life bridge of just five or half dozen months.

Unfortunately the R9 285's naming doesn't make much sense right at present because it's slower than the R9 280X, though it would be easy to assume otherwise. AMD is expected to stage out the R9 280X shortly with a R9 285X version based on the "Tonga XT" role which should feature the aforementioned 2048 stream processors, 128 texture units with higher clock speeds than the R9 280X.

Radeon R9 285 in Particular

Although the R9 285 is based on the latest Graphics Core Next architecture, at its roots you will discover a graphics menu that is almost three years old now (the Radeon HD 7950). Debuting dorsum in January 2022, the 7950 ran for a absurd $450 and was 2d in control to the $550 Hd 7970.

Fast forwards a piffling over two years and we make it at the R9 280, a shameless rebadge of the original 7950. The R9 280 was a lot cheaper thanks to two years of depreciation and a little faster courtesy of a heave clock feature that could boost the core frequency past as much every bit 17% when conditions allowed.

Move alee some other half-dozen months and at present we have a third iteration that'due south clocked fifty-fifty higher and brings about some new features.

Like the Hd 7950 and R9 280, the R9 285 features 1792 SPUs, 112 TAUs and 32 ROPs while the TDP (Thermal Blueprint Ability) rating has been dropped slightly from 200w max to 190w, though the carte all the same requires a pair of 6-pivot PCIe power connectors.

The clock speed has been set at upwardly to 918MHz, 15% college than the Hard disk 7950 but well-nigh two% lower than the R9 280, while the GDDR5 retentiveness frequency has been bumped up to 1375MHz (5.5Gbps) from 1250MHz (5.0Gbps) on the R9 280 and HD 7950.

That all looks great for the R9 285 until yous look at its retention subsystem which sees the 384-scrap retentiveness jitney and 3GB frame buffer severely downgraded. Tonga only offers a 256-bit wide memory bus and the R9 285 comes standard with merely 2GB of memory.

While the retentiveness capacity shouldn't exist cause for warning, the 27% reduction in bachelor memory bandwidth is. Although the memory is clocked 10% higher on the R9 285, it'southward going to be much slower than the R9 280 when comparing bandwidth performance.

On the bright side, due to its higher cadre operating frequency, the R9 285 boasts higher fill-rates and amend compute performance.

With the dawn of 4K gaming upon us you would recollect AMD would be done with small retentiveness buffers. Truth exist told mid-range graphics cards such as the Radeon R9 285 can't really handle textures and resolutions that volition max out a 2GB frame buffer without suffering catastrophic frame loss.

AMD might advertise the R9 285 as beingness designed for gaming across 1080p, but they aren't talking about 4K gaming. The R9 285 can handle the increasingly popular 2560x1440 resolution, at which point it wouldn't be the frame buffer limiting performance just rather the GPU's processing power.

Many years agone at present nosotros proved that at that place was no advantage going from 2GB to 4GB at 2560x1600 using the GeForce GTX 680, and there isn't going to be any difference with the R9 285. That'southward 4096000pixels, and we proved the same was true when displaying 5292000pixels at 5040x1050. Without a doubt you are going to run across custom 4GB versions of the R9 285 and investing in one volition be horribly pointless.

Based on preliminary DirectX 12 specifications as of July 2022, AMD'south GCN-based products are expected to back up DX12 upon its release. That said, the DX12 specification is subject to change without notice earlier release, then I am not sure nosotros can call this "official" support just yet, though AMD is confident enough to already claim and then.