There is almost no info on this chipset. The only reference found was to it being called the "Compactest 386DX Chipset with Cache".
There are 2 chips in this set, and two versions of each chip.
The MX83C305 comes in MX83C305FC and MX83C305AFC.
The MX83C306 comes in MX83C306FC and MX83C306AFC.
We have some motherboards that are identical to each other except that they have one or both parts replaces with the "AFC" part. This leads us to conclude that the "A" parts are just a revision. Previously it was speculated, based on poor information, that perhaps the non-A part was non-caching. This is NOT true. When the 8kB cache is enabled in the BIOS (see picture in files from a board with the non-A chipset), there is a considerable speed difference.
What the difference is, is unknown at this time.
The MX83C306FX part listed in the Encyclopedia (v1.00) is a misprint - mR_Slug
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