Yeah, sucks that Intel legally bullied them out of the CPU market. They had some potential here.

Can you overclock at all? I'd like to see how close you could come to the DX2-66 at 40mhz.

BinaryDemon wrote:

Can you overclock at all? I'd like to see how close you could come to the DX2-66 at 40mhz.

From what I gather pretty much all SUPER33 chips overclock to 40MHz no problem, and that should take it to within a hair of DX2-66. I will try this, but not on the POS ECS 486UL motherboard I am currently using; the ISA and VLB buses are rather flaky even at 33MHz and I doubt stressing it further with 40MHz is wise. I will soon move this build to a new chassis, and while doing that I will replace the motherboard with a higher end SiS board:

I will do the 40MHz overclock on this board in a week or so, and share.

This is a very fast CPU, the U5S-40 performs like a i486DX-50 (and much faster than the DX2-50 because of its bus @ 40MHz).
It is really too bad that the U486DX2 was never released.

I downgraded my slow 486 system from a U5S to an i486DX over the weekend that allowed me to compare the performance of the chips. My experience is that Navratil NSSI benchmark scores are a very good indication of how strong the CPU is for DOS, so I will just present that data, and you can take my word - it is around 30% faster for sure. Doom for example is playable on the U5S but not at all enjoyable on the DX33.

Hats off to UMC. You guys done good.

Some even OC to 50Mhz and beat DX2 then.

How is the FPU performance?

Cheers,

Very interesting CPU.
Never saw a system having one of these though back in the day.

pentiumspeed wrote on 2020-07-06, 19:21:

How is the FPU performance?

Cheers,

It's an SX class CPU, it has no FPU.