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- Newsgroups: comp.sys.amiga.datacomm
- Path: sparky!uunet!wupost!cs.utexas.edu!qt.cs.utexas.edu!yale.edu!ira.uka.de!math.fu-berlin.de!informatik.tu-muenchen.de!unknown!jakobi
- From: jakobi@Informatik.TU-Muenchen.DE (Peter Jakobi)
- Subject: Re: Help on accelerating an A2000 rev 4.x
- References: <2PwJoB3w164w@eastern.COM>
- Sender: news@Informatik.TU-Muenchen.DE (USENET Newssystem)
- Organization: Technische Universitaet Muenchen, Germany
- Date: Wed, 29 Jul 1992 11:12:22 GMT
- Message-ID: <jakobi.712408342@unknown>
- Lines: 44
-
- hao@eastern.COM (Hao Dang) writes:
-
- >Does anybody out there know if the 68030 accelerator boards (ie: Mega Midget
- >Racer, VXL, GVP Combo) will work on a 4.x revision AMIGA 2000? Or do they
- >only work on the newer 6.x revisions? I think I read a message somewhere
- >saying that they wouldn't work because of the different circuitry layout,
- >but I can't confirm this. Please help. I need this information as soon as
- >possible as I am planning on purchasing an A2000 rev 4.x system.
-
- Hello Hao !
-
- Concerning accelerator boards:
- A 2630 25Mhz works fine on a rev 4.1 board. I originally had a 30 Mhz quartz
- in the card, but operation seemed a bit unstable, after I hacked the
- board to 2MB on board (256k*1, 32 chips on soldered onto the old ones - next
- time, even I would consider using newer rams and putting them on the platine
- with the CAS/... logic) using the plan someone named alv provided (not the
- usenet hack). Especially the deinterlaced graphics was flickering and sometimes
- even writing trash-pixels back into chipmem. Updating the board to 4.5 and
- doing one part of the rev.6 'pcb - ``bug-fixes''' from CBM did not help.
- At the moment, after I changed the quartz, everything seems more stable, but
- i cannot say for sure, since the memory problem was not reproduceable. Might
- have been a bus timing problem ...
-
- Display flicker (eg on mouse movements, using the original colorpalette of wb2.0)
- however is the same as before, might be the new agnus is very sensitive to
- miniature changes of voltage...
-
- Anyway, if you buy an used A2000 4.1 and do not intend to upgrade it *again*
- in two years with the newest hardware card requiring an A3000 Zorro 3 bus, or
- whatever, you'll do fine with the old one. 2MB Chip hacks and manufactured
- plug in cards are available at est. less than 400$ , updating yourself might
- cost (ECS: 100$ + cost of 1 or 2M ram), and if necessary, some small changes
- on the board to update it to rev4.5 (well est 10$, estimating German prices).
-
- However I don't think we'll be able to upgrade to the next chipset CBM may release,
- the architecture of the A2000 is simply to old, considering its 'thin' Zorro II'
- bus, slow bus tact rate and ...
-
- CU
- Peter
-
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-
-