AMD announces socket AM3 Phenom II processors

AMD has this morning announced five new additions to its Phenom II processor family, which all feature support for both DDR2 and DDR3 memory.

We were expecting to publish a full review of the new processors today, but this weekend's move into our new headquarters in London has delayed things somewhat after a few teething problems during our testing.

There are three new quad-core and a pair of triple-core processors that have been introduced today, all of which are using the new 45nm SOI fabrication process. Of the three quad-core chips, two are clocked at 2.6GHz - the Phenom II X4 910 and 810 - and a third, the Phenom II X4 805, runs at 2.5GHz.

Lower down the range, the two triple-core processors, the Phenom II X3 720 and 710, will come clocked at 2.8GHz and 2.6GHz respectively. Both feature 1.5MB of L2 cache and a full 6MB of L3 and the model 720 processor is also a Black Edition, which means its multiplier is unlocked.

All of the processors announced today support DDR2 memory at up to PC2-8500 (DDR2-1066) and DDR3 at up to PC3-10600 (DDR3-1333) speeds. There is a catch though - if you're running four DIMMs (to use, say, 8GB of RAM), the supported speeds drop to PC3-8500 (DDR3-1066), effectively nullifying the advantage of DDR3. To be honest, (and we've still yet to finish testing) things are not looking that wonderful for AMD, with DDR3 at 1,333MHz at CAS-7 sometimes affording a negligible performance benefit. AMD itself states "five percent" to us, but this is only in particular applications.

Without expressly confirming with bit-tech, AMD in not so many words has incinuated that it will require a whole new core revision before four DDR3 DIMMs are supported at full speed, so it maybe worth waiting to upgrade. It's unfortunate, because the latest batch of AM3 motherboards, like the Gigabyte GA-MA790FXT-UD5P we used for testing, seem very good.

The 910 and 810 processors are fundamentally the same and the only difference appears to be in cache size - the 900 series Phenom IIs feature 6MB of shared L3 cache, while on the 800 series this is reduced to 4MB. The cache reduction shouldn't have much of an impact on performance - we'll have a detailed performance breakdown on this soon - but it should save you a bit of cash if you want to upgrade.

Pricing for the 910 and 805 hasn't been confirmed yet - it's not on AMD's official price list - but the 810, 720 and 710 are priced at $175, $145 and $125 respectively when purchased in 1,000 unit quantities. Since the Phenom II X4 920 is listed at $195, that means we can expect the 910 to fit in around the $185 price point but it's OEM only and not a boxed model.

We'll reserve our final judgements until our review, but for now you can share your thoughts on AMD's transition to DDR3 memory in the forums.