Advice on Upgrading A4000

[Dr_Righteous]

I'm guessing that GVP SCSI controller is an A2/4000 HC+8, so you should be able to put 8MB of RAM on it.

Be warned, if you do an IDE-CF adapter on that machine, it will use your entire IDE channel (ie no other drive will be usable). Get a SCSI CDROM, it's safer all around as the IDE interface in the A4000 is not intended for ATAPI devices. Old Macs are a good place to salvage SCSI drives.

These are an inexpensive S-Video solution I've been really happy with... http://www.neobitz.com/

This mod works great too http://members.iinet.net.au/~davem2/overclock/a3640.html

[Dr_Righteous]

alexh wrote:
Not true.

You can use an IDE CD-ROM, hard drive or a second IDE->CF adapter at the same time.

If you got one to work, I'd love to know where you got it and what makes it different. There've been plenty of complaints about it shutting down any additional drives on IDE channel. I know I haven't been able to get it to work.

Safer? "not intended"? ATAPI devices work just fine.

If you don't mind using software that can't be registered and times out, then it works great.

This is a good cheap mod, at first I overclocked my A3640 but I do not recommend it. At least not without first replacing the 040 chip that came with it. These boards use VERY VERY old 040 chips which run dangerously hot even at 25MHz. If you can get your hands on an MC68040RC40A with mask L88M you'd be laughing. They run almost cold even without heatsink at 40MHz

Do not dismiss getting a different type of 040 accelerator. The A3640 is nowhere near as fast as even the closest 040 board because it does not support burst mode.

Yes, a heatsink is required and you'll have to try several oscillators to find one that produces stable results. But as long as you socket the oscillator, this isn't a problem. The existing chip will run just fine as long as it's properly cooled.

The goal here is cheap upgrades, not going out and blowing a wad of cash on expensive accelerators.

[Dr_Righteous]

alexh wrote:
I've tried two, one internal. One back panel "external", both work.

Cool, I'll have to try that one. I'd love to be able to put a CF card back in my A4k ad still have access to my hard drive.

Of course you cannot remove the card while hot but that is normal.

Where are these threads?

Most recently...
http://www.amiga.org/forums/showthread.php?t=37837

And no, you don't want to try hot swapping the card. That would be bad.

There are lots of alternatives which do not require registering or timeout, and the one you are referring to can still be registered or easily coerced not to time out with only 30 seconds worth of Googling ;-)

Ahh I stand corrected. Someone finally came out with a working version. Cool.

But requiring software still doesn't explain your words "safer" and "not intended"?

Not intended:
Amiga 4000 with IDE (ATA-1) - 1992
ATA-2/EIDE - 1996
ATAPI - 1998

Safer:
Look, my A4K has jumped up and slapped me once or twice. Don't make Amigas angry!

I understand, but IMHO having performed this operation the difference in speed between a 25MHz A3640 and a 31MHz one is almost imperceptible. Operating System software speedups such as SystemPatch give a better sense of a more speedier system.

I've got mine clocked to 33.3MHz (66.666MHz osc.), and an increase of 8.3MHz seems a speedier to me. Sysinfo thinks so too. I tried pushing it to 37.5MHz (75MHz osc.), but it wasn't stable. 40MHz wouldn't boot at all. I'd like to try it with a 33MHz rated 040 sometime, just to see what happens.