As far as I know all AMD 5x86 chips are write-back compatible, but will also run in write-trought mode for compatibility with older motherboards. If you're having issues getting the CPU to work in WB mode you probably need to set it to WB by jumper setting or from bios.

Sweet. The reason for me asking, was that wikipedia said something about WT or WB when explaining about wich type.
So that is the closest that I have come, to finding out how to identify eighter one of them.

So basically, it does not matter what I set in a bios, whenever I have a 5x86 installed in a Socket3 board.

You still need to set WB cache mode via BIOS or jumper. If you don't set it, L1 will be in WT mode.

kixs wrote:

You still need to set WB cache mode via BIOS or jumper. If you don't set it, L1 will be in WT mode.

On all 486 boards? Thought that it depended on each board.

You can tell from this wikichip page which 5x86 chips had what. Click on each one in the list, and it will tell you how much and what kind of L1 cache the chip had

https://en.wikichip.org/wiki/amd/am5x86

Ampera wrote:

You can tell from this wikichip page which 5x86 chips had what. Click on each one in the list, and it will tell you how much and what kind of L1 cache the chip had

https://en.wikichip.org/wiki/amd/am5x86

Cool. Thanks. It will certainly come handy.
I did not know that page at all. 😀

Took a closer look at the manual for my two 486 boards, and looked closer on the boards.
The FIC board have a dedicated jumper for WB/WT operation.
The Lucky Star on the other hand, have no mention on wich exact jumper is the WB/WT jumper.
Looking in the manual, the different CPU's have that jumper included in one unified setting or so to speak.
All the jumpers that are needed, are just shown under each type of CPU setting.

So yeah... It really differs from board to board, if a dedicated jumper is mentioned in eighter
the manual or mentioned on the board it self. Anyway... Does not really matter, I was only qurious
about if some 5x86 came with WB or all came with WB.

Thanks for info and links everyone. Guess I learned something new today. 😀

brostenen wrote:

Took a closer look at the manual for my two 486 boards, and looked closer on the boards. The FIC board have a dedicated jumper f […]
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Took a closer look at the manual for my two 486 boards, and looked closer on the boards.
The FIC board have a dedicated jumper for WB/WT operation.
The Lucky Star on the other hand, have no mention on wich exact jumper is the WB/WT jumper.
Looking in the manual, the different CPU's have that jumper included in one unified setting or so to speak.
All the jumpers that are needed, are just shown under each type of CPU setting.

So yeah... It really differs from board to board, if a dedicated jumper is mentioned in eighter
the manual or mentioned on the board it self. Anyway... Does not really matter, I was only qurious
about if some 5x86 came with WB or all came with WB.

Thanks for info and links everyone. Guess I learned something new today. 😀

My EXP-4045 does WB/WT through BIOS.

My Luckystar LS-486E does have a jumper for WT & WB mode but, as Ampera has mentioned, some motherboards have a setting in the BIOS for that.

That's strange. All I can see, is that the WB/WT jumper must be one of the JP5 to JP12.
None of them is specifically marked as the WB/WT-Jumper.