IntroductionThe dust has settled on AMD's transition to AM2 and NVIDIA has launched an updated core logic, nForce 500-series, to provide immediate support for the new socket and DDR2 memory controller. What about ATI?
While it's cool to debut brand-new core logic with a new system, it's not always necessary. AMD's choice of HyperTransport as the system interconnect for Athlon 64, combined with the CPUs containing the system memory controller, means that a core logic set for those CPUs isn't tied to the socket the CPU sits in.
That architecture let ATI debut its CrossFire Xpress 3200 northbridge, otherwise known at RD580, with Socket 939 Athlon 64, and now reuse it unchanged for Socket AM2 processors. And since that RD580 northbridge contains a link to supporting southbridges that's basically PCI Express, hanging a number of I/O processors off of RD580 is easy, no matter what socket, CPU or memory is chosen.
All that has led ATI to create the 'Sturgeon' reference board for Socket AM2. It combines the new socket with RD580, and, crucially, its long-time-coming I/O ASIC, SB600. Up to now, discerning board vendors looking to ship RD580 have done so using a very capable southbridge I/O chip from NVIDIA-owned ULi, rather than ATI's own SB450 or SB460 (a version of SB450 that's pin-compatible with SB600).
SB450's seen more than its fair share of criticism, stemming from poor performance in some of the I/O that the IC implements, notably USB. A bit behind in features too, ULi's M1575 is the better choice for a full-featured, enthusiast-class mainboard which is why you'll see it on the best RD580 mainboards on Socket 939.
With SB600 ready and used by board partners for next-gen. CrossFire Xpress 3200 mainboards on Socket 939 and Socket AM2, ATI has its reference board for partners to work with. And if whispers reaching our ears are correct, the Sturgeon isn't just a work in progress; you'll see it in retail form from the usual suspects.
So a snapshot look is worth it, don't you think? Let's see if ATI's AM2 + CrossFire Xpress 3200 + SB600 'Sturgeon' mainboard is worth a squirt.