What's AM2?

As we've mentioned before, AMD's Socket-AM2 is a brand new 940-pin socket that will add DDR2 support for all desktop AMD processors. There will be AM2 versions of Athlon 64, Athlon 64 X2 and Sempron CPUs. All of these are internally known as the Rev F core. When AM2 launches in June, AMD will offer official support for DDR2-533, 667 and 800. As of today, the fastest DDR2 that Intel officially supports is DDR2-667; however, by the time Conroe launches in Q3, Intel will also add DDR2-800 to the list.

What this means is that if you're planning to build a new system later this year - whether it is AMD or Intel based - then you'll be in the market for DDR2 memory. AMD has effectively kept regular DDR-400 quite alive and actually created a market for even faster DDR1 memories with their Athlon 64, but after June that's all going to change. With a single memory standard to support both players in the desktop market, things are going to get a lot simpler. It will also mean that we'll start to see more focus from memory vendors on DDR2, including cheaper variants as well as even lower latency offerings. We'll address whether nor not DDR2-800 is actually needed shortly, but like it or not, if you want a solid upgrade path for the future you'll be looking at investing in some DDR2 memory regardless of whether you choose AMD or Intel.

Alongside DDR2 support, the new Socket-AM2 CPUs add support for AMD's Pacifica Virtualization technology - AMD's answer to Intel's VT. While the two technologies aren't directly compatible, given the respect that AMD has gained over the past few years you can expect software developers to support it. Virtualization will become increasingly more important as time goes on, as we have already seen in recent announcements of Intel VT support on Apple platforms.

The third thing that AM2 brings us is what AMD is calling their Energy Efficient microprocessors. Certain SKUs of AM2 processors will be binned according to their power consumption and grouped into two categories: 65W and 35W. Both TDPs, interestingly enough, are competitive with what Intel is targeting for their 65nm Conroe processors. What's even more impressive is that there will be an Athlon 64 X2 3800+ that's available at both 65W and 35W TDPs, compared to the standard 89W TDP. The chart below will give you an idea of what the new dual core AM2 CPUs are:

CPU Clock Speed L2 Cache Size TDP Options
AMD Athlon 64 FX-62 2.8GHz 1MBx2 125W
AMD Athlon 64 FX-60 2.6GHz 1MBx2 125W
AMD Athlon 64 X2 5000+ 2.6GHz 512KBx2 89W
AMD Athlon 64 X2 4800+ 2.4GHz 1MBx2 89W or 65W
AMD Athlon 64 X2 4600+ 2.4GHz 512KBx2 89W or 65W
AMD Athlon 64 X2 4400+ 2.2GHz 1MBx2 89W or 65W
AMD Athlon 64 X2 4200+ 2.2GHz 512KBx2 89W or 65W
AMD Athlon 64 X2 4000+ 2.0GHz 1MBx2 89W or 65W
AMD Athlon 64 X2 3800+ 2.0GHz 512KBx2 89W or 65W or 35W

In the future you can also expect an FX-64 along with 5200+ and 5400+, but the chart above is what will be launching in the near future (the exception being that the 65W 4800+ that will launch in Q3).

There will also be single core Athlon 64 and Sempron AM2 processors, but we're still waiting for their confirmed specs. Given the specs of the Athlon 64 X2s, you can expect the AM2 Athlon 64s and Semprons to be identical to their Socket-939 counterparts. We'll also finally get retail availability of faster Sempron parts - current socket-939 Semprons are only available with OEM systems.

AMD has already indicated that it will not brand the 65W and 35W parts any differently than the normal 89W Athlon 64 X2s; they will simply have a different part number and carry some sort of lower TDP designation on their box. Of course, they will almost certainly carry a price premium, so that at least should help to differentiate the models somewhat.

As far as major architectural changes go, we haven't been able to find any surprises in any of our AM2 samples. L1 and L2 cache latencies remain unchanged from their Socket-939 counterparts.

You will also notice that AM2 and Socket-939 CPUs appear to carry the same model numbers, meaning that an AM2 X2 4800+ runs at the same speed and has the same cache size as a Socket-939 X2 4800+. Either AMD is being very conservative with its model numbers or we shouldn't expect to see any major clock-for-clock increase in performance with AM2 processors.

Index The Test
POST A COMMENT

105 Comments

View All Comments

  • tony215 - Wednesday, April 12, 2006 - link

    Who in their right mind is going to fork-out hard earned cash for an AM2 mobo, CPU, & DDR2 if there's little to no gain in performance over AMD Socket 939. This review makes depressing reading for AMD fans looking to upgrade, it's obvious that AM2 has little to offer this year, I expect to see many jumping ship when Conroe is released. Reply
  • clairvoyant129 - Thursday, April 13, 2006 - link

    Don't count on many people jumping ships. AMD has a pretty good enthusist fanbase (fanboys mostly). I know Im going to drop my FX-55 for the 2.67GHz Conroe but don't expect many to switch sides... besides, most of these fanboys are probably going to cook up some conspiracy theories to degrade Conroe. Reply
  • Calin - Thursday, April 13, 2006 - link

    I might jump ship to AM2 from my Duron 600MHz processor. For me, a dual channel architecture coupled with cheap Sempron processor and onboard video would make a lot of sense - especially a low power Sempron, if such beasts could be found.
    I am waiting for the AM2 platform (processors, chipsets, mainboards)
    Reply
  • tony215 - Thursday, April 13, 2006 - link

    Calin, by jumping ship I meant switching from AMD to Intel. Let's see what June brings, if this review is anything to go by I don't expect a massive leap in performance from the AM2 platform over current socket 939, People with money in their pockets now aren't interested in what AM2 /DDR2 may develop into in the year 2007. If Conroe lives up to the hype of offering more bang for less bucks ... I'll make the switch, screw brand loyalty. Reply
  • tekkstore - Monday, April 17, 2006 - link

    http://www.tekkstore.com">tekkstore.com Reply
  • clairvoyant129 - Tuesday, April 11, 2006 - link

    My god, that website has to be the most biased **** I've ever seen. Explain Victor Wong's resoluts on SuperPI 1M (21secs) with a $300 processor with an unsupported motherboard and BIOS. I've never seen such fanboyism in my life. You can't believe anything from that website. Reply
  • Anemone - Monday, April 10, 2006 - link

    AM2 may not hold up against Conroe, but until you can buy them in a store, they are vaporware. Intel is late a LOT, so I'm not buying this "don't worry it'll be soon" stuff. Merom prediction: Jan 07. Conroe prediction Oct 06. That's a long, long time for AMD to sell superb chips to a lot of folks.

    $.02
    Reply
  • mkruer - Monday, April 10, 2006 - link

    Everyone is bitching how the Conroe is going to kick AM2 @$$ but the facts of the Conroe are starting to leak out. http://sharikou.blogspot.com/">http://sharikou.blogspot.com/ Does this illegitimate Conroe? No, but it does clarify why Conroe preformed so well in the benchmarked apps. and that Conroe is still more memory constrained then the AM2. The AM2 might just get 4MB of Cache per Core thanks to Z-RAM or at least the K8L server editions sure will. Will the real Conroe to step forward? Reply
  • Shintai - Tuesday, April 11, 2006 - link

    I love how that site only compared Conroes worst results, also the Conroe used crappy memory timings, DDR2-533, preproduction boards, ES sample CPU. Oh, and did we forget its a 300$ CPU vs a 1200$ AMD CPU? Ye we might have forgotten than...didn´t we. Reply
  • mino - Tuesday, April 11, 2006 - link

    Most important it's NON-EXISTENT vs. $1200 CPU.

    Seems many people forget about it.
    Reply

Log in

Don't have an account? Sign up now