The best place to start would be taking a look at the chipset features which are consistent throughout the PT880 Pro, PT894 and PT894 Pro parts and then later explain the differences between each of the chipsets.
Each chipset uses the same "High Performance Memory Controller" (nicknamed "StepUp" for obvious reasons) which contains official support for both Dual Channel DDR and DDR-II memory standards - keep in mind though that you cannot run DDR and DDR-II together on the same motherboard. On the DDR side we have the expected DDR-400 support and on the DDR-II side there is official support for DDR-II 667 which will help increase memory bandwidth when running the CPU and memory with dividers. As mentioned earlier, motherboard manufacturers will be able to choose whether or not they provide DDR or DDR-II or both on their retail boards and we shouldn't have to mention again why this is important (refer to the introduction if you skipped it).
All new VIA PT chipsets contain full support for up to 1066MHz FSB processors which is a fairly big plus as on the Intel side you need to spend extra dollars to obtain 1066FSB processor support from the premium 925XE chipset. The Northbridge and Southbridge are connected through VIA's "Ultra V-Link" bus which provides a plentiful 1066MB/s link.
While I haven't personally had much experience at all with VIA onboard audio, this is an area VIA seems to be pushing with the VIA Vinyl HD Audio solution which is universal among all chipsets. It supports 24/96 resolution outputs along with advanced 3D sound emulation through the integrated VIA Envy24PT sound processor. These specifications are up there with the Sound Blaster Audigy2 which shows that VIA consider audio an important part of their overall chipset product.
Storage is also something VIA aren't taking lightly with full support through the new VT8251 Southbridge for SATAII which increases data transfer rates to 300MB/s which is twice the speed of current SATA drives as well as adds native support for Command Queuing which basically optimizes the way data is collected from the hard drive and hence provides a performance increase. SATAII drives should come on the market later this year.
Through SATAII you also have the ability to use a technology called Port Multiplier which allows you to add up to 60 drives per controller, according to VIA. It sounds very funky but the 300MB/s of bandwidth is shared between all the connected drives so in reality you probably wouldn't use anymore than 2 or 3 at most. Additionally through VIA's revised native V-RAID system you have the ability to use just about every RAID method you can think of (minus RAID 10) including RAID 5 which is RAID 0 + 1 with just three hard disk drives and it is something VIA are claiming they are first to the market with.
The Southbridge which will be used with each of the VIA chipsets is the new VT8251. It provides the support for the SATAII and V-RAID we just talked about along with an extra two PCI Express lanes, eight USB 2.0 ports, 10/100 LAN and 8 channel audio. VIA have told us that the new VT8251 Southbridge will not be featured on retail motherboards until Q2 2005, until then the older VT8237 will be used. It just may pay waiting till boards are released with this newer Southbridge.
That covers just about all of the common features of the new VIA PT chipsets except graphics interfaces but that's what separates all three products so continue on and find out what is different between each chipset.
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