So thank you everyone, especially jesolo, for helping me out with the board's configuration and bringing it to life.

OK, the upgrade CPU is all set. Now i have a 16 MHz 486sx board with 487sx taking over the main CPU. I think it is THE slowest Intel 486 setup possible, and i am very happy about that. I want to compare it to my fastest Intel 386 setup (i386/i387 DX-33 with OPTI 495SLC VLB board) to see if there was any boost in upgrading top end Intel 386 for the first and slowest of Intel 486. I also have similar plans for comparing Intel 486DX4-100 on Intel 420EX board versus Intel Pentium 60 on Intel 430LX board, but i am still waiting for a WB-enabled i486DX4-100 to arrive, i only have a WT version. So, here are a few pics of the final setup:

Interesting to see a 487 in working order 😀
486SX-16 is an interesting chip in its own right though.

Btw, your cache sockets are all empty? Was this purposefully done?

Tetrium wrote:

Interesting to see a 487 in working order 😀
486SX-16 is an interesting chip in its own right though.

Btw, your cache sockets are all empty? Was this purposefully done?

The original CPU is 25MHz unfortunately, but the board lets me chose between 16, 20, 25 and 33 MHz.
The surprising thing about 487SX is that it worked fine on my SIS 496 board on its own, there was no original CPU on the board. I know that 487SX is actually a full blown 486DX chip with an extra pin, but still it looked funny. I needed to configure jumpers for 486SX CPU and BIOS was reporting a 486SX with math co-pro present. Very funny.

The cache sockets are empty because i received the board like that and i don't really know what type of chips i need to install, there is a dirty bit chip that i don't have on any of my other boards, so i've decided to leave it as is, especially since i need it to be the slowest 486 board i have, so no cache is actually a good thing.

Good point about not needing the cache.
But if you ever come across some, it wouldn't be a bad idea to get some if you ever can get a couple for cheaps (for later or perhaps for another board)

I can't remember ever having seen a 487 in the flesh, only read about them and that these were actually just DX's.

Enjoy 😀.

GPA wrote:

The original CPU is 25MHz unfortunately, but the board lets me chose between 16, 20, 25 and 33 MHz.

Then you just could have run the original cpu at 16 mhz, you didn't need the 487sx at all.

Tetrium wrote:

Enjoy 😀.

Thanks!

dondiego wrote:

GPA wrote:

The original CPU is 25MHz unfortunately, but the board lets me chose between 16, 20, 25 and 33 MHz.

Then you just could have run the original cpu at 16 mhz, you didn't need the 487sx at all.

That was the original plan, but since i've managed to get my hands on a 487sx, i couldn't resist putting it in. Besides, just for testing purposes, it would be interesting to see how quake runs there in comparison to 386/387DX-33. I've almost completed test runs on 386/387 system, just cannot make SuperPi run on Win95, there are some libs missing. And I am still waiting for my copy of Q2 to arrive, to see if it runs at all on 386/7 with 8 Megs. After completing all the tests i am planning to run the same set of benchmarks on 487sx-16 to see if there is any difference at all. I suspect the 487-16 floating point unit to show some improvements over 387-33, while the ALUs i think would be on par.