Two things that spring in mind, first off there could be some kind of IRQ conflict with the IDE controller for the HDD or CD, try removing that ESS audio card and doing a bios defaults to make sure that's not the case. Otherwise, it might be bad caps 🙁

I'd try another OS as well, try to install Windows 2000 or XP or even ME just to see if you get similar errors or other BSODs during installation or general instability.

WinXP setup bluescreens with STOP: 0x0000007E.

I tried disabling bios mem caching and shadowing. Also pulled the AGP card and popped in a Rage II PCI card. Still bluescreens. The mobo's appearance is good. Arrived very clean. No visible bulging on any caps or anything. <sigh>

Update: I moved JP4 on the mobo to set CPU/AGP/PCI clk to 95/64/32 (was 100/66/33). That seemed to help. Got Win98 installed, but now it's freezing (kb/mouse, anyway) when it boots up and tries to detect a PNP monitor.

I missed your point about removing the sound card all together, so I guess that one's out. The fact that it BSODs when installing WinXP does not bode well, nor that it manages to go slightly further when using lower clocks. The fact that the caps look alright on the outside, doesn't mean that they haven't died/started to fail, unfortunately it's not always something you can visually make sure of 🙁. Can't think of much else to try, other than perhaps looking at the board and comparing to a high-res photo online to see if you're missing any SMDs.