Reply 40 of 46, by rmay635703
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mkarcher wrote on 2021-07-30, 05:35:BitWrangler wrote on 2021-07-30, 00:54:edit: BTW do ya think the Microsoft spokesdroid had his trollface on when he said the 16 bit bus on the 286 crippled performance since it was on 8 bit ISA, yet the 8086 is also 16 bit, 🤣 ... maybe couldn't get 8088s in that speed grade? I dunno... I feel it wants a V30 anyway.
As I understand it, the microsoft spokesdroid tried to explain that the win from the 16-bit interface of thr processor is limited due to the 8-bit bus, because everything that misses the local memory cache has to be done in 8 bits. The local cache provides some noticeable gain, though. The 8086 is claimed to collect most of the gain you can get from the 16-bit local cache memory, so there is just a very small unused performance potential left to be picked up by the faster 80286.
It’s amazing how large that card is evenfor 1986? considering how little it actually does, 8086 is compatible with the 8 bit bus despite being 16 wide so all the card is doing is implementing a full speed cache.
What I never understood even historically is why this card did not allow you to remove your socketed memory (16/18 bits at a time) and place directly on this card.
Likewise a “local bus” daughter card(s) setup to drive a 8/16bit-10mhz video card or hard disk controller would have made these things fly and would have been no more complex than the cards that let you twin an ISA device along the base of another card.
Heck, even an existing 8 bit card twinned at 10mhz to this card would have reduced bottlenecks (many existing 8 bit cards would run at 9.5mhz)
Even at the time neither would have been particularly complex, just a very curious card, even more curious with Microsoft trying to sell hardware to get Windows sales
