As mentioned earlier, the new VIA PT894 supports Socket 775 Pentium 4 processors that run on 533MHz, 800MHz and 1066MHz front side bus speeds. The chipset works with both DDR (up to DDR400) as well as DDR2 (up to DDR2 667) memory, of course you cannot run both memory standards at the same time. The total amount of memory that can be installed in the PT894 is an amazing 16GB RAM. On Intel's front, the 925X/XE/915P chipsets will support just 4GB RAM. The board PCstats tested came equipped with DDR memory slots only.

The VIA PT894 chipset supports a total of 18 PCI Express lanes; a PCI Express x16 lane for the videocard and two PCI Express x1 lanes that connect directly to the PT894 chipset. There are two more 1x PCI Express lanes available but those run through the Southbridge first. The southbridge is connected to the Northbridge through VIA's Ultra V-Link which runs at 1 GHz through a 16-bit pipeline, and has a total 1066MB/s of bandwidth availible.

VIA is also particularly proud of its new VIA VT8251 Southbridge, which ironically is not used on the PT894 reference motherboard. Like the nForce4 MCP variants, the new VT8251 supports the new Serial ATA II standard and can be used with up to four devices. With Serial ATA you can also run RAID, specifically modes 0, 1, 0+1 and 5 or if you don't want to use RAID the controller works with JBOD as well. The VIA VT8251 also has an integrated 10/100 MAC and if a manufacturer chooses to integrate a Gigabit NIC, they can do so through a special bus that runs through the Southbridge, not PCI bus.

One very neat feature of the new VT8251 Southbridge is VIA's Port Multiplier feature. VIA states that if the Serial ATA II on the motherboard is connected to a "Port Multiplier" type device, the motherboard can actually handle up to 60 SATA HDDs! Of course these port multipliers are not available on the market yet and VIA was quite vague on how exactly this is implemented.

Any luck overclocking?

In the past, VIA chipsets have generally overclocked quite well. Unfortunately we didn't have much luck with the PT880 reference board we tested last year, nor did we have luck overclocking the few KT600, K8T800 or K8T800 Pro motherboards we've tested since then either. With that in mind we didn't have much expectations from the PT894 chipset.

Starting at 200 MHz FSB I slowly raised the clock speed of the motherboard a few MHz at a time. Things were pretty uneventful till we hit around 214 MHz, anything past that the system would sometimes not POST, other times it would simply BSOD during bootup. Raising voltages didn't help, the motherboard only allowed for memory and CPU voltage, both of which have been tested higher already.

I guess our results are not all that surprising, after all this is a reference board. I would expect retail motherboards to overclock higher but we'll have to wait and see before we know for certain.