I have an A7V8X MOBO (KT400). I benchmarked my system before and after installing the Hyperion drivers.
All benchmarks stayed almost exactly the same, except the SiSoft Sandra 2003 File System benchmark increased by about 7%. Seems like it's pretty much just hype.
I guess I'll find out about stability and reliability over time. My system was always perfectly stable with the 4.43 drivers.
If you read VIA's description, it sounds like the performance boost is really for AGP 8x on the kt400 and p4x400 chipsets. The benchmarks they show use a radeon 9700 on those chipsets.
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