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MicroMac Carrera040 in the Mac SE/30
Posted by: xreactx on 2022-09-16 14:24:40
I recently installed Bolle's TwinSpark Clone with an original MicroMac Carrera card in my SE/30. I got it work but the CPU caps out at 32Mhz. I have the correct CPU, but am wondering if I need to upgrade my PSU. Am I on the right track?
Posted by: Phipli on 2022-09-16 14:32:51
The clock speed is fixed by the clock on the board. On those I think the processor runs at double half half or double the clock speed. I think you most likely have a 33MHz board. If you look near the bottom left of the board you'll see a shiny metal component with "66" or similar written on it.
Posted by: Phipli on 2022-09-16 14:34:21
carrera040_front_edit_101098532751238.jpg
Posted by: xreactx on 2022-09-16 14:37:08
Oh wow... That was a noob overlook by me. Mine says 16mhz.
Posted by: Phipli on 2022-09-16 14:40:13
Oh wow... That was a noob overlook by me. Mine says 16mhz.
Ah right, your's does double the clock then. A 32MHz 040 is pretty quick in an SE/30 anyhow. At most 21% difference, but in reality closer because they're both restricted by the 16MHz bus.
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