A3000 chip swap

[toddbailey]

OK, upgrade time and a couple of questions.

1. i'm having scsi issues (machine doesn't fully boot, scsi channel lockup, issues with removable media, drives not found, etc) after research turns out I have the bad version of the scsi controller "00-04" proto, sources say I need the newer part. I found a few on ebay but also found an amd replacement of the same part number for much less in cost. any opinion on if the amd part will work and fix the scsi issues. pin out is the same.

2. ZIP memory types, I want to fully max out fast memory on the a3000, research tells me to use fast page mode memory to allow the installation & operation of an add on cpu cards such as the a3640. The a3000 currently has 8 static column 1m x 4 installed. I have a retina display card that has 8x 1mb x 4 fpm chips 70 ns, the A3000 has 8x 1mbx4 static column. Any one know if I can swap scm with fpm and use the scm chips on the retina card? this will minimize the number of fpm chips I'll need to buy. Note my a3640 vers 3.1 in my a4000 (68040@25) doesn't work in the a3000. I'll probably need to replace the pals/gals to the latest vers.

3. over clocking the a3000, it currently has a 16 mhz 68030, I would like to replace with a faster cpu, the old chip will need to be unsoldered and a faster one installed,
Any thoughts on using a cpu socket, will one actually fit?
Has anyone ever has success in doing so? is the a3000 limited to a 25 mhz cpu or will 33 or faster work with the proper clock modules installed? what clock modules will I need to replace? will I need to replace the 68881 with a faster mmu perhaps a 68882 instead?

thanks

[brett71]

For #1, I can say with certainty that the AMD chip will work just fine. I made this upgrade on a A3000 I owned a while ago and had no problems with it.

[alexh]

The person you really want to talk to is called SpeedGeek. He's a big A3000 hardware hacker/guru.

research tells me to use fast page mode memory to allow the installation & operation of an add on cpu cards such as the a3640.
The a3000 currently has 8 static column 1m x 4 installed.
my a3640 vers 3.1 in my a4000 (68040@25) doesn't work in the a3000. I'll probably need to replace the pals/gals to the latest vers.

I think you answered your own question It doesn't need upgrading. It is because you've got static column RAM fitted. Static Column doesn't work with the A3640 if you are using a Ramsey-04 and a DMAC-02. There is a Ramsey-07 and DMAC-04 upgrade where you could run static column with an A3640. But you'll never find a DMAC-04.

Remember that the A3000@16MHz cannot use the Rev. 11 Super Buster required for Zorro-III DMA (gfx cards, scsi cards etc.).

16MHz A3000 users have reported a lot of success just replacing the U104 oscillator for a 50MHz one, changing the jumpers to the 25MHz setting and running at 25MHz with a 16MHz 030/68882. No soldering a new CPU

http://eab.abime.net/showpost.php?p=897122&postcount=13

[attle]

Originally Posted by toddbailey

I found a few on ebay but also found an amd replacement of the same part number for much less in cost. any opinion on if the amd part will work and fix the scsi issues. pin out is the same.

Linky?

[alexh]

http://www.ebay.co.uk/itm/AM33C93A-1...item25974e385c

It is identical to the WD33C93A-PL 00-08

[toddbailey]

The AMD scsi controller comes in 2 speeds, 16 mhz and 20, will it matter which one I use ?

I found both but for the 20 mhz part the distributor has a min order qty. 1/2 a dozen as I recall.

[toddbailey]

Originally Posted by alexh

The person you really want to talk to is called SpeedGeek. He's a big A3000 hardware hacker/guru.


I think you answered your own question It doesn't need upgrading. It is because you've got static column RAM fitted. Static Column doesn't work with the A3640 if you are using a Ramsey-04 and a DMAC-02. There is a Ramsey-07 and DMAC-04 upgrade where you could run static column with an A3640. But you'll never find a DMAC-04.

Remember that the A3000@16MHz cannot use the Rev. 11 Super Buster required for Zorro-III DMA (gfx cards, scsi cards etc.).

16MHz A3000 users have reported a lot of success just replacing the U104 oscillator for a 50MHz one, changing the jumpers to the 25MHz setting and running at 25MHz with a 16MHz 030/68882. No soldering a new CPU

http://eab.abime.net/showpost.php?p=897122&postcount=13

thanks for info, the a3000 was last upgraded with the latest super buster -11 to allow the use of a fast lane z3 card.
You say it doesn't work on the 16 m 3000 but I haven't had any issues with the z3. lucky or a fluke,

never found the DMAC-04 for sale, already have the ramsey 04 installed
btw: I went ahead and ordered a set of fpm memory, and a replacement scsi controller.
Maybe some day I'll have all the upgrades done and be able to actually use it other than diagnostics, I'll have to try out the new clock setting thanks for the suggestions

[toddbailey]

Originally Posted by alexh

http://www.ebay.co.uk/itm/AM33C93A-1...item25974e385c

It is identical to the WD33C93A-PL 00-08

yeah that's the one on order, but paid a bit more, 12 bucks us


I'm also finding pal/gal updates for the a3640 card, but for now since it works in my other Amiga (a4000) there it will stay, unless I find a sweet deal on a ppc/68050 or 60 card.
as far as cpu swapping goes, if I were to have the modification made it would be for the fastest 030 available, assuming a 50 mhz part would work in a near stock a3000 board.
going from 16 to 25 doesn't sound like much but for the cost of a clock chip it's work the exercise.

hopefully with the new scsi controller and a memory upgrade I'll be able to use the machine a bit more.

[alexh]

Originally Posted by toddbailey

the a3000 was last upgraded with the latest super buster -11 to allow the use of a fast lane z3 card. You say it doesn't work on the 16 m 3000 but I haven't had any issues with the z3. lucky or a fluke

Lucky. Read this post from Dave Haynie from 1997

https://groups.google.com/forum/m/#!...8/f_aShADB0P8J

[toddbailey]

I found a company that does board assembly and repair locally, I sent them an email asking how much to do a chip swap and a re-ball on a sony ps/3 hopefully I get a quote in my price range, If affordable, I plan to replace the stock 68030fe16 with something a bit more capable. I was thinking a 33, 40 or a 50 mhz replacement. the 33 is under 20 bucks so a painless purchase. Once installed, slowly ramp up the clock speed and find a middle ground between slow and flaky. I was thinking separate clock speeds of 32, 50, 66, then maybe a second pass at 80, 85, 90 & 100.

Any one done this before and care to comment?

[alexh]

You've got too much money. You can see from the posts that all you need to do is swap the crystal and jumpers to operate at 25MHz. Most A3000 users have reported no problems over clocking their-16 rated part to 25mhz

25MHz is the maximum the A3000 can be reliably run at. There is a thread on EAB about over clocking the A3000 to 33MHz but it explains why it's generally not stable

[NMI]

You can't overclock a 68030 and A3000 in the same way as you can a more modern cpu/computer.
The moderboard, chipset and cpu are all closely tied together by the same clock, so if you rise the cpu-clock you rise the clock for everything else at the same time. Your 16HMz cpu will most likely do 30+ MHz without any issues, but the motherboard will probably not make it past 30MHz reliably.
Get yourself a decent accelerator card instead.