[Sheeplator]

Nearly correct. The DX/4 100MHz had a 33MHz bus. The DX/4 75MHz had the 25MHz bus. I remember well because I had both.

[bombcar]

Now I remember being annoyed that it wasn't the DX/3 as it should have been!

[einr]

Especially since when actual clock quadrupled chips eventually came out they had to call themselves ridiculous things like ”5x86” instead of DX/4. (The Am5x86 133 runs at 4x33 MHz)

[cout]

I think 5x86 had more to do with marketing than anything else, because the Pentium had already been on the market for a while when the Am5x86 came out.

[einr]

I think it’s a bit of both. It absolutely tried very hard to pretend that it was a ”586” (Pentium class) but also ”5x” is right there and implies that if the DX4 is 4, this is 5.

The full name on the chip on some of them is ”Am5x86-P75 DX5-133” which implies a lot of things, some of which are flat out misleading (it does not get very close to ”P75” performance)

[Zardoz84]

I had one of these back on the day. A very fine 486