Just picked up this neat board. This photo is the seller's.
I use an APC Predator I Plus as my main 386/486 board right now and it gives excellent performance. That board has a Symphony Haydn II chipset, and a similar layout with two VLB slots at the bottom of the board. The jumpering is simple, and the board seems really robust and very fast. It's easily the most stable and complete 486 board I've used, and it's the most interesting hybrid board I've used. Unfortunately, the 386 side of things does not like 486DLCs very much, and I've had issues with cache coherency that I am still working out. Everything seems stable now--except SpeedSys.
This board, however, intrigued me for two reasons: (i) it's another APC board, so why not trust it there; (ii) the chipset.
I have NEVER seen this chipset before. Has anyone heard of it or seen it before?
I referenced the almighty mR_Slug's Chipset Database and found some neat things out about this chipset:
- it dates to 2/10/95, so it's apparently a very late VLB-only chipset
- it supports the Cyrix 5x86 natively (or seems to do so?)
- the EIDE controller is integrated into the chipset
- it supports interleaving on the RAM side of things
- apparently it can do L1 in WB, so that's nice (if it's stable)
- apparently it's "VESA Local Bus 2.0 Compatible."
That last bullet point, right there, sold me on the weirdness of this chipset. I have read that VLB 2.0 is marginally different to the extent that the contrasting factors pertain to burst reads and writes, but apparently VLB 2.0 is 64-bit and also supports 50MHz officially within the spec. While I realize that a 486 probably can't take advantage of the former, and the latter is mostly off the table, it's still intriguing to me. (I guess I'm a VLB nut 🤣) I don't know if this means that this board contains an actual VLB 2.0 implementation but, to my knowledge, other than integrated devices sitting on the VLB bus, there are no VLB 2.0 compliant cards.
I wanted to share the datasheet for this chipset, but it only fit on my Google Drive. Here's a link, if you want to check it out. I've done the Adobe text recognition conversion, for your convenience.
When the board comes, I'll probably make a proper thread.
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"Never trust a computer you can't throw out a window." - Woz