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> Paul (Blittersoft) do you have anything you can add to this?

This from Mick:

The 22MB/s speed they are getting is limited mainly by the '020 bus and generally slow 68k interface (the '020 bus speed is 14MHz therefore it isn't able to transfer more than about 18.6MB/s), the '030 will obviously be able to push data out faster but probably still needs to use a PCI write buffer.  A PCI interface doing single transfers will work at around 12-20MB/s, the BoXeR will do bursts so peak throughput with 4 cycle burst will be able to hit the 70-90MB/s throughput levels.  The 68060 can
probably just about manage to provide data to keep up with this, although it has to fetch instructions and stuff which means its not trying to push things on the bus the whole time.  The single chip design BoXeR board will easily sustain this as the PCI bus will be decoupled as will the 68k and PPC/memory
busses (ie it has 3 separate busses).  
This means the 68k can do a very short burst from SDRAM (using a 64-bit read FIFO), get off the bus freeing it up for a DMA controller or the PPC which could be driving things at the 100MB/s+ speed
and then the 68k can do a short burst to the PCI bus with a write FIFO meaning that the PCI bus operates at full speed.  Its hard to say exactly what it will achieve without real-world testing, but the 2.1 may well be able to sustain >100MB/s PCI transfers with an optimum set of operation.

Note that real world tests are not guaranteed until tested on final
hardware...!

So you see, BoXeR, being a modern design throughout, offers a big advantage.
 

Regards,
 

Paul
Blittersoft