Some Amiga 2000 Newbie Questions

[Huxley_D]

Hi guys!
I recently managed to win an auction for a Commodore Amiga 2000 from a local seller. The seller was great (and may be a source of more vintage gear in the future!), but not particularly knowledgeable about this particular machine. The A2000 I got is a plain-jane mode, but at some point in its life it underwent some significant upgrades:

First, it received a "Great Valley Products" Impact A4000-HC+8 - with a 70 meg SCSI hard drive. The slots on my board are empty, but the drive is fully functioning, loaded with software, and boots flawlessly!

Second, it got a Commodore-brand "A25000" RAM board with 2 megs of DRAM chips soldered on.

Finally, this A2000 has an A-MAX Macintosh emulator module. This strange rectangular brick connects (externally) the the rear of the A2000, and when outfitted with genuine ROM chips from a Mac 128k or 512k Mac, allows the Amiga to natively run (early!) Mac software. The 1st-gen A-MAX that I have will boot up to Mac OS 6.0.3, according to some info I found online.

I've gotten the system booted up, but I only have an older Commodore monitor (designed for the C64 and C128), so the Amiga 2000 is displaying a pretty shaky image in greyscale. I'm going to start scrounging online for a monitor more suited to what this machine is capable of! Also, we're experiencing a pretty good lightning storm here in Albuquerque, and the Amiga is clearly unhappy with the currently unstable power, so I'm going to play with it more tomorrow.

The A2000 I got actually came in its original box (in pretty good shape too), with the keyboard, mouse, and original power cord. The A-MAX (along with some other software and games, and a 2-channel hardware audio mixer / input box!) all have their original boxes, manuals and disks.

All-in-all a great find, and a really fun addition to my collection!  However, as I've only ever played with A1000's and 500's in the past, I've got a few questions about this machine that some of you might be able to help with:

1.  What's the best / easiest way to determine which model or revision this 2000 is (as in Rev. A / B / C)?

2.  What's the best / easiest way to determine what ROM this 2000 has, and what would be the ideal ROM for this system?  Perhaps a related question - what would be the idea version of the OS for this system?

3.  With the 8 RAM slots on the GVP board, how much RAM can I add to this thing?  I'd guess 8 megs, but I think I read that some of them could use more...

4.  Does anyone know a source for a PDF of the user manual for Amiga OS and / or the user manual for the 2000 itself?

5.  How does one determine exactly which CPU module is in a 2000?

Thanks for any help you can provide, and please bear with me as I get up-to-speed with this thing!

Huxley

[Huxley_D]

Hi Save2600,

Thanks for the awesome info!  Here are a few notes, mostly based on your tips:

There is a sticker near the rear of my A2000's mobo that reads "REV 6.2" which seems a good indication that it's a later-revision motherboard.  Also, the etched text near the front of the motherboard says "REV 6" - I missed this on my initial look-over due to the thick coating of dust on the board itself!

I just removed the "BOOT" jumper on the GVP drive board and fired the system up - the boot screen is displaying a neat animation of a floppy going into the drive, and the text "2.0 ROMS (37.175)" - I assume this means I have Kickstart 2.0?  I just ordered a KS 3.1 ROM chip on eBay, but it'll be a while before it gets here.

The power supply in this machine seems to be working fine.  The flakiness I referred to was almost certainly due to the lightning storm that was causing my power to bounce up and down while I was first tinkering with it.  It's run fine several times since then.

If you can possibly provide another bit of info, I could use a bit more help:  The only Commodore-friendly monitor I have at the moment is a 1902A.  I'm connecting the mono video out on the A2000 to the RCA-style input on the 1902A.  With this configuration I'm able to use the A2000, but only in black-and-white (or is it greyscale?), which is clearly not ideal.  Is it possible to get full color from the A2000 to this screen (most likely with a different type of cable), or should I just start looking for a 1080 or 1084?

Thanks again - this is proving to be a really fun project!

Huxley

PS  I'm in Albuquerque, NM USA, and my Amiga has a sticker in the inside-rear that reads "WEST CHESTER BURN-IN" - is this an indication of where my A2000 was born?

[Huxley_D]

Just a minor update, but a cool one nonetheless:  I just stopped by the shop of the person I bought my A2000 from, and they actually had another A2000 for me!  This "new" A2000 is in pretty poor cosmetic shape (far worse than the first one I bought), but it could prove to be a valuable source of replacement parts over the decades to come.  I haven't had a chance to pop it open and see what's inside, but from looking through a gap in the rear of the unit there appears to be at least one (possibly two) expansion boards in there.

It's currently sitting in my trunk, but once I'm home tonight I'll take a close look inside and see what I might find!

Huxley

[Huxley_D]

just a small bit to add to the good news:

If your A2000 had the Kickstart 2.0 from "birth", then you likely have an ECS equiped one (think of it like an A2000+ .. same as A500+) - not earth-shattering, but you would have the "super-hires" Denise and the Agnus ready for 2Mb chip memory.

Tom UK

That's quite interesting!  Is there any way to tell if it's an ECS model other than the factory ROM?  Is there something on the motherboard itself that would give it away?

Huxley

[Huxley_D]

How exciting for you! Opening up *ANY* Amiga can garner some interesting finds. Here's to an 060 card lurking inside   :-)   lol

Well, I just opened up the second A2000, and it's an interesting box.  It's been pretty completely gutted - it's a case, mobo and 2MB RAM card.  No PSU, no drives, heck, no drive bracket.  On the other hand, the battery has minimal leaking (no visible damage), it's a REV 3.9 motherboard (which might make it a pre-production model?), and it has an interesting Buster Tower which my REV 6.2 machine lacks.

All-in-all a nice find, and for the $10 I paid for it, I'm happy to have some spare parts for my "main" A2000.

One additional question - would there be any reason not to use both of the 2 meg RAM cards in my main A2000?  Would they conflict, or would I just have 4 megs of usable RAM?

Thanks for all the insights, guys!

Huxley

[Huxley_D]

Rev 3.9? That one's pretty uncommon. Makes sense, though - you said the guy you got it from used to be a dealer?

Check out info on board revisions from each of the hardware databases.

The guy I bought both systems from is a local electronics recycler - a great guy, but his specialty is tearing stuff apart, not restoring vintage gear!  I don't know anything about the original owners of these Amigas (I'm assuming they're from the same person, but I'll probably never know for sure), but they clearly had an interest in audio recording, as the "main" system not only came with a simple 2-channel mixer, but has quite a bit of audio software on the hard drive.

Huxley