Issues with VIA's Apollo Pro133A

In our last test we could show that VIA's Apollo Pro 133A chipset has become a serious competitor to Intel's i820. Especially the lower costs of the platform plus the much lower cost of the actual memory (PC133 SDRAM vs. PC800 RDRAM) speaks quite strongly for VIA's latest solution. Still there are several issues with this chipset that I'd like to discuss here.

A - The AGP-Driver Of Apollo Pro 133A

You might have seen it elsewhere or heard about it, some motherboards with the Apollo Pro 133A seem to have serious performance problems in 3D-applications. I saw references claiming that particularly the Asus P3V4X performs very badly in e.g. Quake 3 Arena. The results published by me in my article 'Showdown at 133 MHz FSB ' did not reflect this problem and thus I received a few questions.

When I did my first runs of the P3V4X I had used VIA's latest set of drivers, the 4in1-drivers rev. 4.20. Those drivers include the AGP-driver (viagart.vxd), some inf-files and VIA's latest bus master driver for ATA (IDE) hard drives. The 3D-performance with this set of drivers was very low indeed and for me much too low to be true. Therefore I spend quite a while trying to find out what was hindering the 3D-performance of the P3V4X, because it was obvious to me, that I could not possibly publish those - obviously wrong - results. After a while of trying I found the reason for the bad performance. It is VIA's AGP-driver. I had already been puzzled why Asus delivered the motherboard with VIA's 4in1-drivers rev. 4.17 , since those drivers seemed very out of date. Installing those drivers instead of rev. 4.20 solved the mystery. The P3V4X scored perfectly well with the AGP-driver of the 4in1 rev. 4.17. The driver sets 4.18 - 4.20 lead to horrible AGP-performance though and are to be avoided. Thus I recommend using rev. 4.17 for the time being, while we are trying to find the reason behind this strange behavior.

That's all there is to it. The wrong AGP-driver leads to horrible 3D-performance.