AMD finally goes DDR3

AMD IS LAUNCHING something quite interesting today, five socket AM3 socket CPUs without any mobos to go with them. The cool part is that because of their socket compatibility, you don't need a new mobo or RAM for the upgrade.

First, the meat of the announcement, there are five new CPUs, the X3 710, X3 720BE, X4 805, X4 810, and the X4 910. All are Socket AM3/938 parts, compatible with AM2+ and AM3 boards, and all of them pull 95W. Rather than go through a long explanation, here are the raw specs.

The raw specs

If the naming seems somewhat obtuse, well, it kind of is. The basics are pretty obvious, the speeds start at 2.4GHz, numbering on an even 100 multiple, and go up five for every 100MHz above that. The X3s are all 7xx series, and so far come with 6M of L3 cache. The 8xx series X4s come with 4M L3, and the 9xx have 6M L3. Basically, you can actually figure out the specs of the CPU from the name, just don't bring up the 940@3.0GHz, that is a AM2+ chip, or something like that. Other than one spurious data point, the chips are refreshingly decodable.

A 940 and 2 938s, can you spot the difference?

If you can't decode them, and need to tell an AM2/AM2+ CPU, AKA DDR2 based Phenom from an AM3, just count the pins. The top left is a DDR2 Phenom II 940BE with a 810 to it's right, and a 720BE on the bottom. Notice there are four sets of pins missing from the grid, and there are 940 of them on the 940. Really, count them, I didn't. The two AM3/938 chips have 938 pins, the top right and bottom left holes have three pins missing as opposed to two on the 940. Also, the AM3 chips have a darker shade of green substrate.

As this is being written, the chips are in the Inq test rig, and benchmarks are churning away. We should have complete numbers in a few hours, but for now a few initial impressions. First, they went in to our test machine – a Gigabyte GA-MA790GP-DS4H with 2G of Kingston 1150MHz DDR2 (KHX9200D2K2/2G) and a Sapphire 4870X2 GPU – without a hitch. The latest BIOSes were flashed, and it all just worked.

The numbers have not been fully run yet, much less tabulated, but initial impressions are quite good. They look to be about equal or a little better than their AM2+ counterparts in most power figures, and right on top of them in performance. The initial big question was, 'do you take a hit without DDR3', and the answer so far is a flat out 'no'. They even look to be a little more power efficient on the same hardware as the earlier parts.

That brings us back to the lack of AM3 boards, and why AMD would launch without them? When asked, several AMDers all said the same thing, basically because they could. There is no down-side to the new chips when using DDR2, and you can move to DDR3 whenever you want.

DDR3/AM3 boards are almost done, the hard part of the transition is the memory controller, and that is fully baked in the CPU. We are being told that the BIOSes, however, still need quite a bit of TLC before they are ready for public consumption, that is the sticking point. The DDR3 boards are a few weeks out, and shouldn't be all that expensive when they hit the market.

All in all, the launch today puts out some decent chips in the meat of the market, the $100 to $200 bracket. It should come as no surprise that the parts fit in the middle between several Intel competitors in price and features. The 810 is positioned against the Intel Core Number Numeral Q8200, a 2.33GHz 1333FSB 4M cache model. The Phenom is $5 more, but also has almost 300MHz more speed while overclocking pretty well. This should give the 810 a slight edge in most cases.

On the triple core side, things get interesting. The closest Intel parts are the E7400 for the 710, and the 720BE slots in between the older E7500 and the newer E8400. Both give up 200MHz to the Intel parts, but have twice the cache of the 7x00 parts and equal that of the 8400. The selling point is simple: the AMD chips pack an extra core.

This makes for and interesting dichotomy. On older and less threaded games, the clock of the Intel chips will carry the day, but for newer more thread aware games, the third core should easily tips the scales. If I was going to chose the most future-proof part, it isn't a hard one at all, the X3s win.

The launches today are solid but not earth-shattering. AMD finally has DDR3 parts on the market just after DDR3 prices nosedived. While this is more likely due to the economy in general, it does work out well for them. The five chips launched today are all solid, affordable parts with good compatibility on older AM2+ boards. They make a solid upgrade from Phenom 1s, and AM3 compatibility means they are totally future proof when it comes time to go DDR3.

There are no down sides to these parts that we have found so far. µ