First post, by LuigiThirty
I picked up a Tektronix K1103 protocol analyzer recently because it’s full of transputers. Once I got a peek inside, though, it was clear that it was also going to be super upgradeable. No less than six ISA slots in a portable chassis!
But... it seems to be unusually slow despite my upgrades, according to the big benchmarks. I’m thinking it has something to do with the motherboard, which I can’t find any info on.
The motherboard is a Microdesign SC i486 Rev.A4. It has a VLSI VL82C486 chipset and an Award Modular BIOS 4.20. It came with a 486DX, I dropped in an Am586 133MHz. It’s identified by the BIOS as an “Unknown-50” but CHKCPU confirms it’s running at 133 (33MHz FSB and 4x multiplier).
I installed a GD5426 video card, a Sound Blaster 16, and an NE2000 NIC. (It also has three Siemens transputer cards that have no info online.)
Even if I pull all the cards except for the video card, I get 32.2FPS in 3DBench and Doom doesn’t even run at full speed? According to the benchmark spreadsheet, even with an ISA video card and no L2 cache I should be getting way more than that. I dropped in a 486DX2-66 (which the motherboard does recognize properly) and I get 27FPS in 3DBench.
Memory bandwidth is 31MB/sec according to CACHECHK and all the speeds seem fine.
Does anyone have any info on this motherboard or its jumper settings?