Does the SB850 really have a PATA controller?

[loophole]

Just a curiosity question really but one that I can't seem to find a good answer for (or at least one that satisfactorily scratches this particular curiosity itch ).

In all the hardware review sites that discuss AMD's 800 series chipsets I've seen the same block diagram over and over again that shows the SB850 with a single PATA channel coming off the southbridge. TR has two diagrams showing this, one for when the 890GX debuted and another for the 890FX pseudo round-up:
http://techreport.com/articles.x/18539
http://techreport.com/articles.x/18825

But all the boards that I've seen and the reviews that I've read (mostly 890FX boards) seem to be using an auxiliary third-party chip for the PATA controller (if they have a PATA port at all).

So, I'm wanting to know: if the SB850 does actually have a single port PATA controller, why aren't motherboard makers using it? Are the chipset block diagrams out of date and AMD has actually removed the PATA controller from the SB850 as Intel did a few Southbridges ago? Or is there some issue with the SB850's PATA controller that prevents board makers from using it (like the USB problems on AMD's early 768 southbridges)?

Or, maybe a simpler question: has anyone found a board that's using the SB850 that has a PATA port that is being controlled by the SB850 rather than a third party controller? But the more interesting question is if no manufacturers are doing this, why?

Thanks!

[Usacomp2k3]

Maybe they figure that having just 1 port is kinda pointless, so they put an aux chip on that gives 2.

[loophole]

Maybe they figure that having just 1 port is kinda pointless, so they put an aux chip on that gives 2.

But all of the boards that use an auxiliary chip use one that only has a single PATA port.
Some common choices I've seen are:
* VIA's VT6330 which gives one PATA port and two Firewire 400 ports
* JMicron JMB361 which gives one PATA and one SATA port
* JMicron JMB363 which gives one PATA and two SATA ports
* JMicron JMB368 which gives just a single PATA port

I'm starting to think there isn't actually a PATA controller on the SB850; but I could be completely wrong and there's some simple explanation for why nobody is using it...