VIA KM133 Socket-A Chipset: Final Battle of the Value Chipsets

DVD & Hard Disk Performance

As you’ll remember from our SiS 730S Review, one of the major selling points for the chipset was that it’s integrated SiS 300 graphics core supports both motion compensation as well as iDCT (Inverse Discrete Cosine Transformation) in hardware.  This helps keep the CPU utilization while playing a DVD stream down to a minimum, provided that the decoder (in this case WinDVD) supports the features. 

Unfortunately, it seems as if the KM133 still uses the Savage4’s hardware motion compensation, which isn’t helping much in this case, providing extremely high CPU utilization figures.  You would be better off using a plain software decoder or trying to dig up an older software DVD decoder that would’ve shipped with a Savage4 based card that can properly take advantage of its hardware motion compensation engine. 

Another big issue that came up with the 730S Review was the extremely poor disk performance of the 730S under Windows 2000.  It turns out that the poor figures were due to poor driver support under Windows 2000, while under Windows 98SE the 730S can offer almost 80% of the maximum ATA/100 specification (which is reasonable once you take into account driver/OS overheads).

However, the KM133 would not provide us with greater performance than a 35.2MB/s burst rate regardless of what OS we were running under (using the 686A Southbridge).  The KM133 definitely needs to be paired up with the 686B Southbridge in order to compete with the 730S in terms of hard disk performance.

At the same time, the 730S needs improved driver support under Windows 2000 so that there isn’t such a great performance discrepancy between the two OSes.