Introduction

Mid-2004 the SLI technology with which had launched nVidia nForce 4 chipset again, ATi with its CrossFire technology followed by end May 2005 on the chipsets of RD400 (Intel) and RD480 (AMD) and Intel also read to his i955X for ATI’s CrossFire technology license and sent last week without great attention to the i975X chip set in the race, which can drive two graphics cards now elegantly on the Northbridge.

And VIA?

Already in January the Taiwanese group with the PT894Pro introduced a chipset for Intel processors, which at the time was the first for the Intel platform, which could operate more as a PCI Express graphics card. The technique is heard on the name “VIA DualGFX Express Graphics”. Lacks only a counterpart for the Socket 939 made by VIA. Currently the company for this socket offers only the K8T890 chipset with PCI express support, which has only SATA 150 available due to the now obsolete Southbridge (VT8237).

This is to change from now everything, because VIA presents for the Socket 939 the K8T900 chipset with the new MultiChrome technology. This joins the long-awaited VT8251 South Bridge, which has to offer a lot of new features. We introduce the new chipset in this article. Naturally, a mainboard test will follow as soon as first subjects reach our laboratory with the new chipset.

The Northbridge

An important feature of the new K8T900 chipset is the PIN compatibility of the Northbridge of the older VIA K8T890. To help save the mainboard manufacturers development costs, they can but accept parts of the layout. To the K8T900 supports all current AMD processors for Socket 939, in particular the Athlon 64, the Athlon 64 X 2, the Athlon 64 FX, the AMD Opteron and the AMD Sempron. Of course, processor and Northbridge are connected via a 16-bit wide and clocked at 1 GHz HyperTransport link.

The Northbridge has over 20 PCIe lanes, that are distributed among five controller. So other four x 1 lanes can be addressed in addition to the 16 x connection for a PCIe graphics card individually. This offers for additional RAID or network controller onboard components. In addition to x 16 configuration the lanes on two x 8 lanes can be split to enable simultaneous operation of two PCIe graphics cards.

VIA the MultiChrome technology introduced with own subsidiary company of S3 Graphics for this along with the appropriate graphics processor earlier this month. From a purely technical perspective, the K8T900 supports also ATis CrossFire-or NVIDIA SLi technology. Only the graphics cards drivers of the two producers are the successful use in the way and improvement is unfortunately not in sight.

To achieve the highest performance with the two graphics cards, RapidFire technology developed VIA which is supposed to work yet energy-saving with high-bandwidth.

As usual provides VIA also benchmark results. Now, should you consider skepticism this with a healthy dose, does not know you but the exact benchmark sequence and the used driver. The results are very promising, but must confirm in practice.

The southbridge

We come to the long-awaited new Southbridge from VIA, the VT8251. One of the most interesting innovations is implementing two PCIe x 1 lanes, which can be combined naturally also into a x 2-lane. Thus, a total of 22 PCIe lanes are distributed on seven controllers from North and southbridge available. As bandwidth 5 GB / s of North arise so each direction and 0.5 GB / s with the southbridge.

The North – and southbridge interact back with the well-known ultra-V-link connection, a 16-bit-wide and synchronized with 66 MHz Bus, which provides a range of 1066 MB / s. VIA here relies on proven technology and changes to a HyperTransport link connection, nVidia how she used the nForce family.

The “drive station” has been completely redesigned. It now offers SATA II with 300 GB/s, can handle Native Command Queuing (NCQ) and staggered spin-up. In as far away from the SATA controller can be addressed by Windows XP without drivers, and so a disk operating system installation is possible, we can say at present still not with certainty.

Also added is the complete RAID support of the modes 0, 1, 0 + 1, 5, and JBOD. VIA four independent controller has integrated to ensure highest performance. So easily mixed insertions of SATA are II I and SATA devices possible. On Windows this is VIA RAID tool available, the RAID associations can be created or transformed without loss of data. Of course, still four ports for PATA devices up to 133 MB / s are available.

The VT8251 can handle up to seven PCI slots and support for LAN connections with up to 1 GBit / s is also given. Eight USB 2.0 ports are available in terms of USB. The HD audio support of the VT8251 is certainly a plus. Various onboard sound solutions for the it should is possible with vinyl audio. Starting with the rudimentary AC97, about VIA vinyl HD audio with 7.1 sound and 32-bit, 192 KHz support up there for VIA vinyl envy gold 24 PT.

Conclusion

He VIA K8T900 makes a solid impression. Both the North and the southbridge are as regards the ports very flexible. A largely free configuration of the PCIe lanes in both parts of the chip set speak for themselves. Hopefully, the long-awaited VT8251 South Bridge keeps what it promises. Again, flexibility is the key word: LAN 10 Mbit / s up to a GBit / s are possible and also at the onboard sound the mainboard manufacturer has the option.

VIA the last in the boat of the multi-GPU chipsets for Socket 939. remains now only hope is that one has used the time in the labs to develop a sophisticated and powerful chipset. VIA presented benchmarks Let’s hope for some. Also, the merger of two S3 chrome graphics cards must demonstrate its performance yet. Here, also independent measurements are to be seen.

Let us hope that the former leader for AMD chipsets in this segment can make well again lost ground. But one should be clear: even the competition is not sleeping. While nVidia with the nForce 4 SLI x 16 appears to be already a little enteilt, zetar ULI and SIS from the second row with new products.