AMD 785G: No 7.1 audio here folks.
In our AMD 785G
launch coverage we wrongly assumed that because AMD had upgraded its HDMI bandwidth to "1.3", its UVD core to "2.0" and its IGP to "Radeon HD 4200", that this was directly comparable to the "2.0" version numbering used on the desktop Radeon HD 4xxx series of graphics cards. Unfortunately, this doesn't seem to have been the case, as AMD confirmed with us this afternoon that the audio block on its 785G northbridge has not changed since the 780G - it still only supports DVD quality, 5.1 channel audio at most: S/PDIF throughput, basically.
It does not
allow 7.1 channel LPCM audio that we had previously stated. This multichannel HD audio is key for HTPC enthusiasts with prosumer audio equipment. Admittedly, this is a relatively small number of people, however it's a feature both Intel and Nvidia which have supported on their chipsets since last year.
Since the launch, Anandtech
has discovered that since retail drivers and products have launched, this multichannel HD audio support has either gone missing or was never included in the first place.
Unfortunately due to lab limitations on our part, we couldn't check this for ourselves, so we took AMD's hints at a complete feature for granted. In hindsight we should have asked specifically, rather than assumed the full UVD was ported from the desktop products.
However, it has to be said that it's not the first time AMD has shipped products with sneaky differences. The Radeon HD 4890 for example was shipped to us with different clock speeds than was advised in the documentation provided, and then there's the Radeon HD 4770, where the reviewers' sample was almost a completely different product to what end users ended up being able to buy. While we will endeavor to be more vigilant in future with the detail, it doesn't bode well for AMD to act this way - not just for the reviewer:manufacturer relationship, but also for readers who want clear and accurate coverage of products they're considering buying.
We have amended the articles accordingly to represent the correct information: a guide to the AMD 785G chipset
, and a review of Gigabyte's GA-MA785GMT-UD2H motherboard
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