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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Ancalimon on July 28, 2020, 01:48:27 PM
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Is it possible to have both connected to an A4000T? I want to get a Mediator and a Radeon.
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yes, they will both be separately addressable and available to the system at the same time.
my first and main concern would be the RTG software you chose to run. does Picasso96 have a Permedia2 driver? or does CGX4 have a mediator/Radeon driver?
either way, i suspect after running the cybervisionPPC, you'll be disappointed with the basic graphics performance of the radeon/mediator combo.
the only advantages the radeon has are:-
1. up to 64meg of usable graphics ram - anything above that gets added to the fastram pool - but it's anything but "fast" - and the 64meg Graphics ram limit wipes out any point in having a 256meg card except for a "who has the bigger numbers" competition.
2. able to handle screen "bitmaps" larger than 2000x2000 pixels - the P2's bitmap handling and ramdac speed became an issue trying to run large screens with a decent bit depth.
3. digital output.
downsides of the Radeon.
1. No warp3D driver/support. and looking at the forums - getting an idea of what shenanigans have gone on, and promises have been made/broken, i can guess that this will never happen.
2. performance. i pulled my mediator and radeon out and plugged in an CyberVision64/3D using the A4k's original zorro3 busboard. all numbers on P96 speed were up with the cybervision, and general "user experience" was much better.
3. have to faff around with another thing (mediator) to get a thing working.
but then, all of the above is purely my experience - your mileage may vary etc etc.
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I thought Radeon on Amiga was faster at everything except lowres 3d accelerated games.
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First of all Zorro3 card are limited to 13.5 MByte/s, due to buster chip, so anything connected to zorro iii, slot will be limited to that speed.
https://en.wikipedia.org/wiki/Amiga_Zorro_III
Zorro2 is connected directly to the CPU, and on board bus, you can’t really clock up system bus, because it’s connected to all kind of custom chips that do not support high clock frequencies.
So the best way avoid this problem is to connect the graphic card directly to the accelerator, this way the accelerator, provide high speed bus access to the graphic card, while not messing up onboard timing.
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Yup, in a nutshell.
it's why i'd love someone to reverse engineer the CPLD chips on a Cvision or G-Rex and do another production run. i seem to recall some benchmark program getting 50MB/s on the ol' cyberstorm3/blizzardPPC bus. so best case scenario, for the mediator, is it's only 3 to 4 times slower than the G-Rex, or B/Cvision cards. and that's before the obvious hardware differences between the permedia chip made in the 90's, and radeon chip made in the 00's.
i could put some legit numbers up there to test this but the thought of faffing about with putting a PPC/bvision machine together again and what boingbag version works with what version of cybercraphix.... eeesh. no thanks.
having 64Meg graphics ram tho, and just not having to worry about how many screens with high bit depths/resolutions... and also not stressing about cooling... almost worth it...
--edit-- some numbers i did for another forum. same OS software, same graphics software
A3k = A3000, Cyberstorm3/060, Cvision64/3D. A500 = A500&Vampire2. A4k = A4000, A3640, Mediator, Radeon9250 - not the best CPU i admit, so will revisit when either a TF4060 or Warp4060 becomes a thing.
operation A3k A500 *A4k*
RectFill 2889 4261 6722
RectFillPattern 2842 6158 5875
WritePixel 147969 301582 57870
WriteChunkyPixels 741 6158 403
WritePixelArray 730 6072 386
WritePixelLine 30072 36449 11630
DrawElipse 9874 24698 4920
DrawCircle 10743 25527 5975
Draw 14644 6768 1328
DrawHor/Ver 24624 16067 9811
ScrollRasterX 162 313 1259
ScrollRasterY 160 389 1330
Text 10351 12596 2849
BltBitMap 8660 8530 6229
BltBitMapRastPort 7058 7135 3368
BitMapScaling 75 548 66
Openwindow 103 172 20
MoveWindow 392* 1135* 43
SizeWindow 117* 261* 11
ConOutput 371 652 104
ScreenToFront 61 61 60