A3640 memory/performance issues

[darksun9210]

yeah we do seem to be in a bit of a sellers market for the last year or three!

looks like i'm waiting for the TF/icomp/apollo pot of gold at the end of the rainbow 
but i'll keep my ear to the ground in the mean time

[AmigaHope]

Burst mode is where you can transfer an entire cacheline (16-bytes) with only one setup cycle(s), as opposed to having to call out each 32-bit read/write. i.e. after the setup then each cycle you squirt another 32 bits down the bus for the next 3 cycles. This only works on a synchronous bus obviously, and the 68040/060 and 68020/030 buses are different in other ways as well. The A3000/A4000 fast slot is on a 68020/68030 bus. This is normally only handled by the caches but you can explicitly take advantage of this as well on 040/060 with MOVE16.

The A3640 has no local memory to burst to, and runs on a dissimilar bus. Even you run it synchronous to the motherboard bus (Speedgeek does this to minimize wait states), it has only bare-bones glue that will not let you burst across it. 

[paul1981]

How fast is the ZIII RAM compared with motherboard RAM? I'm guessing it's slower and the 16MB isn't enough to hold your OS boot and your 3D rendering program, hence the program code get's shoved into ZIII and it's doomed to run slower. Perhaps your OS needs streamlining a bit? Just a thought that's all, as those figures seem a bit extreme - the 040 should be rendering quicker than the 030. Didn't people buy A4000/040's for quicker rendering times?

[darksun9210]

Good info @AmigaHope , i've heard of "burstmode" for years, but never actually understood what it was!

Z3 ram is slower than mainboard ram. i'll try some bustests to compare if i get a chance this evening

@paul1981 good point, i'll try a minimal boot to see if i can keep everything in the 16meg. maybe even pull the z3 ram card out just to see what difference that makes if any.
To be honest, an 030@50 with local ram outgunning an 040@25 without local ram both does and doesn't surprise me
The Blizzard i have with an 040@25 and local ram shows what this CPU could do if supported properly i guess.
an A3630 does 10:34:31 (hrs:mins:sec) with a 25Mhz 882, and putting a 33Mhz crystal on there brings that down to 7:50:54

[darksun9210]

Just as a reference, this is my bustest output (10^6 byte/s):-
A4000 A3640 buster rev11
mainboard ram:-
readw 11.1
readl 11.5
readm 11.3
writew 6.0
writel 6.0
writem 6.1

Zorro3 ram (bigram256)
readw 7.5
readl 7.6
readm 7.6
writew 3.9
writel 3.9
writem 3.9

mediator graphics card ram (radeon 9250 128meg)
readw 2.5
readl 4.9
readm 4.9
writew 3.7
writel 7.3
writem 7.4

chipram
readw 2.3
readl 4.7
readm 4.6
writew 2.3
writel 4.6
wrltem 4.6

[DamageX]

That is shocking.

[darksun9210]

as additional
Bustest output (10^6 byte/s):-
Mediator removed, standard busboard backplane re-installed, and Cybervision64/3D results.
(Glad to see both the Phase5 and DCE versions of the card need the card guide piece of plastic removed from both an A3k and A4k. anyway...)
readw 2.4
readl 4.8
readm 4.9
writew 3.1
writel 6.1
writem 6.2

now i distinctly remember getting 14meg a sec across the zorro bus when i had my cyberstorm2/040 card. so i'll keep hanging on for something similar.

[cehofer]

I am building an Amiga Mediator Tower out of spare 4000D parts I have.  I have am using the A3640 CPU card V3.1.  Why does it take 30 seconds to start booting?  If I hit a stop watch with a reset, it will not try to access the floppy or bring up the BIOS screen if you hold the two mouse buttons down until 30 seconds everytime.  I remember something about this delay.  How can I fix it?

[TribbleSmasher]

do you have any IDE harddrive installed yet? If not, the machine waits for spinup of one just to be sure there is one present - or not.

[cehofer]

Is there a way of shutting off the IDE or do I just have to install and IDE drive?  I have the GVP SCSI Impact HCII right now.  I don't remember it doing it when I was testing with my CyberStorm III card.

[kolla]

http://amigakit.amiga.store/product_info.php?products_id=831