ZorRAM vs. Busters

[Zac67]

Deneb can run in DMA or PIO mode. DMA mode doesn't work with onboard or Zorro III SCSI due to Super Buster limitations.

[Zac67]

offtopic, apologies. But does "onboard SCSI" include the SCSI in the A3000?

Yes, unfortunately.

Eg. is DMA mode of the Deneb supported on the A3000?

Yes, but only with CPU board SCSI. More than a single bus master messes up the Buster.

[Zac67]

A Buster 11 will reportedly not work at 16 MHz! According to Dave Haynie, it was neither designed nor tested for that speed.
You'll need to upgrade to 25 MHz (which I would've done long ago) - but why change anything when it's working fine?

[Zac67]

Actually A3640 is clocked at 25MHz, but I don't know if Buster is using the same clock signal. If it is then my problem is solved :afro:.

Sorry, missed that. The A3640 runs the board at 25 MHz, so it should be fine with the Buster 11 - but you should keep it in the back of your head in case you remove the '040 one day.

[Zac67]

;-) Buster 7 lacks all DMA support, and therefore also almost all DMA related "features" found in Buster 9 and 11.

So, in a nutshell - ZorRAM is fine with Buster 7? As is Deneb (PIO only)?

[Zac67]

The two 16 MHz A3000 I 'upgraded' (swapped oscillator and changed jumper settings) ran fine right away.

Why is it that ZorRam owners always talk about the quantity of their memory and not the speed of their memory? (not much to say I guess).

ZorRAM is the fastest you can get with Z3 RAM - somewhat slower than onboard but faster than DKB and Fastlane. Your best bet is an accelerator with RAM which will be way faster.