Building the perfect A2000: part 4

As we ended the last instalment of our journey, we were heading into 1992 and had spent over £4300 on the Amiga 2000 we originally bought in 1988. It wasn’t without reason, and we have a fairly powerful machine to show for it – faster than an A3000 with most of the same features such as SCSI and loads of RAM, plus we’ve had years of use out of it too.

(You can skip back to Part 1 where we buy the machine and fit some memory, Part 2 for a hard drive or Part 3 for CPU upgrade if you need to catch up)

But the recurring theme, and one you’re probably familiar with, is that once you add a bit of power or capability in one area you expose the next weakest link. We added memory, and it became a chore to load those new larger programs from floppy. We added a hard drive, and got fed up of waiting for the processor. We added a faster CPU and, well let’s just say it’s becoming a bit tiresome to wait for things to happen on the screen. It’s time to add a graphics card!

Stage 6 – Graphics

All Amigas, from the A1000 onwards, had the capability of impressive (for the time) graphics out of the box. It’s what set them apart from PCs of the era, they were a multimedia machine that could display high resolution images with hundreds of colours and control individual pixels. PCs of the 80s were very limited in terms of colour palettes especially, and many 8-bit home micros of the era could just about produce slow graphics modes, preferring to output text based screens. But by the 1990s, PCs had caught up with the VGA standard being first introduced on the IBM PS/2 in 1987 and just a year later, this became SuperVGA with higher resolutions and more importantly a colour palette to rival the stock Amiga experience. Initial costs were high, but by the early 1990s this was more affordable tech and it was cheap and easy to equip a PC to outstrip the Amiga in terms of graphics.

One of the issues was that fantastic multimedia “out of the box experience” of the Amiga that sold so many machines, also became its downfall with users feeling confined to the graphics capabilities that the machine came with. This was especially true of the A500 with everything built into the machine and no route to expand them, but thankfully we invested in a big box machine with our beloved Zorro slots – already used for both SCSI and RAM – and this can be pressed into use as a graphics expansion by slotting a dedicated graphics card in.

So what are the advantages of expanding our graphics capability? Firstly it means we can juggle more colours on screen, at higher resolutions. If you’ve ever fired up DPaint on an A500 or A2000, you’ll remember that you’re limited to 32 colours (or 64 if you use the Extra Halfbrite colours in DPaint 3 or later, muddier versions of the main 32 shades) and this is simply a limitation of the Amiga chipset that was so ground-breaking in the mid to late 80s. You can create some beautiful images, but you will struggle to create anything truly photo-realistic. An alternative is HAM modes which uses some tricks to display 4096 simultaneous colours, but very slowly and you wouldn’t want to try moving them around on screen. A dedicated graphics card isn’t subject to those rules, it can display 16 million colours in 24 bit mode because the image doesn’t have to pass through the Amiga chipset; instead it’s generated and output by the card itself. You can also manipulate the image – you can paint using those millions of shades and see realtime effects with things like airbrush tools and gradients in the same way Photoshop users in the modern day would be familiar with. When people talk about how the Amiga was used back in the day for creating graphics for film and TV, a 24-bit graphics card was a really important part of the process to create an image realistic enough to blend in to live footage.

Secondly, the same graphics chip can be put in charge of drawing the Workbench screen you’re used to, and in fact any program’s interface. We call this RTG – ReTargetable Graphics, and it describes a way of “hijacking” (or Retargeting) calls from the operating system to the native Amiga chipset asking it to draw things on screen, and passing them through the graphics card. The benefits here are that the graphics chip on the dedicated card will have routines for drawing things like lines and boxes, the type of objects that a user interface features heavily. When something appears or moves on screen, what’s happening inside the computer is that bits are being changed in memory so if we have a chip that’s been specifically designed to understand what a “line” or “filled box” is for example, we can ask it to put one of those into memory (and hence on screen) in a much faster time than the Amiga chipset could.

This technique of being able to run Workbench, or other programs, through the graphics card also allows that same benefit of more colours and higher resolutions. Where Workbench was once 640×256 in PAL modes, now it can be set to resolutions such as 800×600 or 1280×1024 – around 8 times as much screen area. This is made possible by having dedicated memory on the card; where our A2000 has 1MB of Chip RAM and this has to be shared across graphics and sound, a graphics card could have 1, 2 or even 4MB dedicated to just the image you’re seeing on screen. If you’re asking for a screen four times the size, it stands to reason you’ll need four times the memory.

Another reason for choosing an RTG card is that the video output is a more standardised “VGA compatible” signal. Amiga monitors expect a signal of around 15KHz, meaning it scans across the screen 15,000 times a second. It was chosen for the Amiga as it’s closely related to TV signals, but by the 1990s PC monitors were falling rapidly in price and these expect twice the input frequency, at 31KHz. If you wanted a larger, higher resolution monitor they were far more easily found from a PC dealer, but they can’t be connected to the Amiga without either a scandoubler (taking the video signal and resampling it to match the VGA standard) or an RTG card that has been designed to work to this frequency.

RTG cards are a little bit more specialised than accelerators and SCSI controllers so we have a bit more of a limited choice, but still you’d have been able to pick up some of the more productivity-focused magazines of the time and see head to head comparisons. Names such as Picasso and Piccolo would have been familiar, along with Retina and Spectrum. Interestingly it’s one area Commodore themselves never really expanded into, with just a very obscure card (the A2410) mainly intended for Unix workstations being released and subsequently having drivers engineered to work in AmigaOS. That contrasts with the SCSI cards, RAM expansions and accelerators we’ve already looked at where Commodore had those add-ons available all the way through the life of the A2000. That should give you a good idea of how specialised we’re getting and what a small proportion of users would go this far with their upgrades – the built in capabilities really were good enough for the masses, whether they were gaming or using it for more serious purposes.

Here we’ve gone with a Picasso II card from German manufacturer VillageTronic. Don’t let the name fool you, there was no Picasso I but these are almost a de-facto standard for Zorro 2 graphics and for good reason. They’re built around a Cirrus Logic GD5426 chip, which featured in many PC graphics cards of the same era and were well known as being a reliable, cost effective choice. As this chip does the hard work in moving memory around and drawing to the screen, it’s just as at home in an Amiga as the PC and the rest of the card contains the logic to allow this to be controlled over the Zorro bus. The card back in the day would cost around £300, in our modern recreation it cost £180 from AmiBay.

You’ll notice from the pictures that this card has two monitor connections, both of them the 15-pin high density D-Sub type. On a PC this might allow you to connect two monitors for a dual screen setup, but here it’s for a different reason. The RTG arrangement in an Amiga can redirect the operating system to our speedy new card, but games and other non-Workbench programs won’t know anything about this new card and continue to output via the Amiga custom chips (with Denise picking up the task of video output), which will go nowhere. The first connection goes to a monitor as you’d expect, but the second connection is a loop from the Amiga 23-pin output into the Picasso II card which will intelligently output whatever is needed. If the operating system is displaying via the RTG software, that will be shown but if you start a game, the RTG goes black and the native video starts up, and the card acts as a passthrough down the same cable to the monitor.

There is a complication here though, as the Picasso II doesn’t change the frequency of the Amiga’s video output and as we mentioned earlier, that isn’t compatible with standard PC monitors. If we fired up a game, for example, which knows nothing about RTG then it would want to display via the native Amiga chipset at 15KHz. If we feed this into the Picasso II, it would switch the signal but then we’d be feeding that 15KHz into an SVGA monitor which wouldn’t know how to display it. We’d need to invest in a multisync monitor for that to work, which feels like it’s adding needless cost – a 15″ PC monitor at this point in time is around £200, where an Amiga compatible multisync one is potentially twice that in the case of a Commodore 1960 that can do the full range of screenmodes that both the Amiga, and Picasso II can output.

For now, we’ll tackle this by ignoring the problem. It’s worth mentioning that we never covered the cost of a monitor in the first place – something which has been pointed out by readers of this series! It’s not a huge problem though as dealers were regularly bundling a basic Commodore or Philips monitor with the A2000 for RRP, so let’s assume we took that deal and have had one sat there all along. Phew, that’s that dealt with. But now we’re going to add a generic PC monitor to the system whilst we set everything up, with that plugged into the Picasso II and the original monitor remaining on the 23-pin native Amiga connector for now and then come back to this issue later.

Now we turn to the software, a major part of the equation. Luckily from Workbench 2, Commodore made this type of add-on much easier with some specific changes to how monitors work and no longer do we need to hack and patch into the OS. The most common Amiga RTG software is called “P96”, a shortened version of “Picasso 96” reminding us that it was originally supplied with the Picasso II card, and this is still software being developed in 2022 by Individual Computers. The name has changed due to unwanted attention from the family of the famous artist, but from its roots with our card it now supports almost every card available thanks to a modular system of card plug-ins.

Back in the day however, there would have been alternatives – Phase5 “Cybervision” cards came with their own competing software called CyberGraphX (still common with some cards, and being developed for MorphOS), and there was also a system called EGS from GVP which aimed to replace Workbench entirely and needed replacement apps that were EGS-aware. Thankfully the intervening 30 years have been kind and smoothed out these bumps, leaving P96 as the de-facto standard for classic Amigas.

The software is what brings this all together – it allows you to define screenmodes, combinations of resolutions and colour depths, that will then appear in the standard Workbench screenmode requester. For example you could configure a 800×600, 16 bit colour (65,000 colours) screenmode and save it to the list. That screen will then be available not just for Workbench, but for any program that lets you choose a custom screenmode. The Picasso II will go all the way up to 1600×1280 if you limit it to 256 colours, plus a whole bunch of less eyeball-straining modes useful on regular size screens such as 800×600 and 1024×768 which are available with more colours. From that point it’s seamless – any program you’ve told to open on a P96 screen will be routed through to the graphics card.

Sadly it’s also going to require another upgrade. For reasons of compatibility, and to retain the last shreds of sanity we have, we’ve gone with the latest version which is a commercial product from Individual Computers. This is only compatible with Workbench 3.0 or higher – luckily this is 1993 and we can fit a Kickstart 3.1 chip which could have been purchased from an Amiga dealer. Version 3.1 brings the benefits of 3.0 which was released on the A1200 and A4000 but is compatible with older machines such as our A2000. We covered the upgrade process in a previous instalment when we fitted Kickstart 2.05, needless to say this is the same deal; fit a new chip, and install Workbench from disk.

So with the card installed, we switch on – remembering at this point we’ll need a monitor still connected to the 23-pin port as that’s where the video is still coming from. Install the software, define the screenmodes, and tell Workbench to use it. At that point, a PC monitor connected to the Picasso will burst into life with a beautiful, high resolution Workbench image. We immediately start getting the benefits – Workbench will feel quicker but also allow us to view higher resolutions on a nicer monitor. Word processing will feel less clunky with finer resolution to on-screen text, and you’re afforded more screen area for working with files and Workbench windows. For most users this is the real benefit of an RTG card as by the 1990s Workbench was feeling quite cramped with default screenmodes such as 640×256, or 640×512 if your eyes can stand interlacing and it sometimes seemed a shame that an operating system that was built around multitasking rarely had enough screen space to display programs side by side. Even dragging and dropping files around in Workbench was often a challenge with the windows taking up so much space. Not any more! Here we’re running the card at 800×600, quite a modest resolution for our 15″ monitor, but the difference is vast and allows for much easier use of Workbench.

We can also reap the rewards with some everyday software. We’ve got a couple of examples below – Directory Opus is our go-to file manager and the extra pixels on screen give a far better experience when organising files compared to the rather cramped default view. Or perhaps you’re writing a document; we’d previously installed Pen Pal to demonstrate the benefits of a hard drive, and now we’ve upgraded this to the successor Final Copy it’s clear how much more visibility you get of the document you’re editing compared to the standard PAL High Resolution screen. And this is just two examples of apps that need no patching or modification, or special versions – they just open on their own screen in the normal Amiga way, but now we can select a P96 screenmode in a way that’s completely transparent to the program.

The other benefits are more specialised and require rather expensive software such as TVPaint or Brilliance – two of the leading 24 bit paint packages that will let you create and manipulate photorealistic images. But if this was your area of expertise, it would once again feel like the Amiga is leading the pack – remember the chip on our graphics card is identical to many PC cards at the time, but we’re adding in a fully multitasking operating system a couple of years before Windows 95 would land.

It’s not all roses though. We’ll start to see some incompatibilities with older software; a great example is the landscape generator Vista Pro which is not only hard-coded to only open on a native Amiga screen, but will crash if Workbench isn’t an example of that screenmode! Some other programs will get confused about the new mind-blowing range of colours and look distinctly strange as they expect to choose from only 4 shades, too. But the big issue is just the sheer amount of programs, and pretty much every single game, that doesn’t have any way of letting you choose a screenmode. These will always want to display via the Amiga’s own video connector as we mentioned earlier, requiring an expensive monitor.

Thankfully, there is a solution and it’s so closely related, it forms the second part of this instalment.


Scandoublers

The Amiga 2000 has an almost hidden connection, far away from the Zorro and CPU slots inside, on the far side of the power supply. This is a video connector, and it features all the signals present in the external 23-pin monitor port (plus more, for controlling certain bits of hardware like Genlocks). A neat solution to our problem of not being able to display the Amiga modes on the VGA monitor is to slot a “scandoubler” in here. This is a device that takes the 15.6KHz Amiga signal and doubles it to the 31.2KHz that a PC monitor would expect. Anything displayed on the Amiga video port is now also coming out of the scandoubler at a rate that we can feed into the Picasso 2 card, and swap between exactly as it’s meant to.

We’re once more into the realms of quite esoteric hardware so there’s not many options, but whilst building this machine I happened across a 3-State Multivision device which was perfect. Compared to the huge Zorro cards we’ve been using it’s fairly diminutive but it does the job of picking up the video signals, remixing them into a VGA compatible signal and then outputting via a handy slot in the back of the case where a 15-pin High Density connector sits. It works by storing the picture and outputting it twice for every image so just uses a bit of speedy memory to constantly read and write, and to the user there is no difference – no lag, no stuttering and you’d be hard pushed to know it was even in the machine. It’s entirely hardware based with no drivers needed, so much so it will even work for the Kickstart “Insert Disk” screen.

As shown in the gallery, we can use a short VGA cable to feed this in and job done – when the Picasso senses that we’re using a native Amiga mode instead of RTG, it swaps over to the passthrough but that is now the correct type of signal for the monitor so after a half-second delay or so the image appears. When we use an RTG screenmode, the Amiga video output goes black which the Picasso II card takes as a signal to move back to its own video – again, within just a fraction of a second.

The Multiway device is also quite useful in that it picks up the audio signals also present in the video slot (that aren’t in the external 23-pin video port) and has a small amplifier on board, with a volume knob and 3.5mm output. Quite useful for headphones, or to use some passive speakers.


Conclusion

With an RTG card we’re well into the world of power Amigas now – this is not just a mildly upgraded system, this is perhaps in the top few percent of machines around in terms of speed and capability. And once more we’ve leapfrogged what’s on offer from Commodore’s A3000 which came from the factory with a very mildly upgraded “Enhanced Chipset” (or ECS) which offered a few higher workbench resolutions, but nothing like what we can now use. And we’ve also ticked the final box that the A3000 had over us, which is the ability to use VGA monitors with that built-in flickerfixer provided by the Amber chip (and it’s the only machine in the history of Commodore to offer that feature). It seems only right to celebrate by pimping our Workbench screen with a full install of the legendary Magic Workbench icon pack!

In terms of price, on our way into this instalment we were at £605 in modern times, representing a spend of £4354 back in the day. We’ve added £180 for the graphics card, and £40 for the scandoubler. A 15″ monitor was just £20, and Kickstart 3.1 was £18.
Vintage adverts show that the graphics card would have been £300 in 1993, the scandoubler 479DM (or around £200) and the monitor £200. Kickstart 3.1 was a £30 upgrade.

As we close out on 1993, our modern spend is £863
It would have set us back £5084.

We’ve got a bit of a problem now though. Time is marching on and 1993 is notable in Commodore history as the birth of the AGA machines; our target for the past few years has been the A3000, but now the A4000 is available from dealers. This machine offered a distinct change in direction, being designed for cheaper upgrades and lower initial cost. In next part part we’ll evaluate how we stand up against that new challenger as well as install a few more upgrades, so join us soon.

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