Geek, that Business Disk WinMark99 did catch my eye when I first read page 5 of the Digital Web 3D review. And the reviewer didn't say anything about it!
I can interpret what that Penstar review did imply. [I gave a broken link in my original post.]
http://www.penstarsys.com/Reviews/mobos/tyankt/index.html
"The CD that comes with the board has an older version of the VIA 4 in 1 drivers . . . ."
and
"One thing missing from the manual is the explanation of the VIA 4 in 1 drivers that need to be installed to give the system optimal performance in IDE and Graphics dependent applications. One page could easily summarize what to do with the software and what effect it has on system performance as well as stability."
My inference: The Digital Web 3D Review was using poor drivers.
Page 3 of the Penstar review does the HD Tach 2.61 bench. The reviewer says:
"Tyan was one of the first companies to really tweak and perfect the IDE performance of the VIA Southbridges, but here they fall a little short of their own ideals. On the Trinity K7 and the Trinity 400, the burst rate hovered around 59 MB/sec and the CPU utilization was down around 4%. There still needs to be a bit of work on the BIOS for this board, but it is nearly there."
So ATA 66 may be a bit disappointing on the Tyan Trinity S2390. I plan to get a 30G IBM ATA100 @7200. So if I went the 2390 route, maybe I'd get a Promise EIDE controller anyway.
Stability is my number-one concern, because I have to admit I'm just a newbie doing my first build of my own system. So my opinion is like a fan circulating hot air in a case.
My current system is a PII-350 I bought from Polywell Computers. That Win98 box seems to have a Gigabyte MB and has been very stable.