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Quadra Quirks

The Quadras and PowerBooks are out and I actually saw some of them recently at the dBUG Hardware SIG, thanks to a local dealer. By now most people probably have a decent idea of what each machine offers, so I won’t talk about that any more. Instead, I want to discuss what’s weird about each machine, what you will want to know before you buy one, and that sort of thing. For this information I’m indebted to Cary Lu, the author of The Apple Macintosh Book from Microsoft Press. Based on the invaluable information he provided at the meeting, the latest edition of the book should be well worth buying and reading.

Let’s start with video. The Quadras have internal video that supports all Apple monitors, VGA monitors (using the same adapter as used by the Mac LC, and Super VGA (SVGA) monitors. In addition, there is support for a one-page landscape display (the current Apple one-page display is portrait), a category currently filled only by an E-Machines 16" monitor with ROMs dated after July of 1991. Cheap upgrades are probably available from E-Machines. Unfortunately, the VGA and SVGA emulation is done strangely and only works at 60 Hz for VGA and 56 Hz for SVGA. So you can hook up a cheap VGA monitor, but it will flicker, since flicker-free monitors generally run at over 60 Hz. The Quadra 700 comes with 512K of Video RAM (VRAM) and the Quadra 900 with 1 MB of VRAM. Both can be upgraded to 2 MB of VRAM for greater speed and 24-bit color for larger monitors. The VRAM will be expensive, but the since the Quadras have their own VRAM, they won’t slow down when using internal video (unlike the IIci which does slow down to varying degrees when using the onboard video since the onboard video takes a share of the RAM). Graphics will be even faster since some of the graphics acceleration from the Apple 8*24 GC card is built in, although that card can accelerate all NuBus video cards, which the Quadra internal video can’t do. The Quadras also include support for NTSC and PAL, although I don’t know the details. For the PowerBooks, I’ve already mentioned the SCSI box that will provide external video support from Radius, and other companies will do this too. However, the internal RAM slot may provide a faster connection for an external monitor and several companies have already announced monitors that connect in this way.

RAM in the new Macintoshes is equally interesting. Both machines ship with 4 MB of RAM, but Apple only advertises the Quadras as being able to expand to total of 20 MB in the 700 and 64 MB in the 900. The Quadra 700 has 4 MB of 1 MB SIMMs soldered on to one bank, with one bank of four slots open, whereas the 900 comes with four banks, one initially full of 1 MB SIMMs, but with nothing soldered on. Apple’s claims that these Macs can only go up to 20 MB and 64 MB (using 4 MB SIMMs), may turn out to be conservative since true 16 MB SIMMs have been informally tested and work fine. I say true 16 MB SIMMs because composite 16 MB SIMMs that are made up of four 4 MB SIMMs may not fit into the Quadra case, although at least one company, Newer Technology, claims that they have composite SIMMs that will fit. No point in bothering with 2 MB SIMMs particularly since they are expensive, but if they fit inside, they should work. Cary Lu said that 64 MB SIMMs were still in the research phase, so there’s no need to worry about them for some time yet. In addition, I gather that there is a 1 gigabyte limit built into the MacOS, and that will become an issue eventually as well. RAM for the PowerBooks will be expensive because only a few companies make it so far, and they will require the more expensive pseudo-static chips. Upgrades will be available in 2 MB, 4 MB, or 6 MB sizes from numerous vendors, and each PowerBook can only have a maximum of 8 MB. PowerBook RAM looks like it will cost between $100 and $150 per megabyte.

The Quadras don’t come with the IIfx’s strange black terminator (the Quadras use normal ones) or the direct memory access (DMA) to SCSI that Apple used in the IIfx (which, by the way, is no longer in production, although there are plenty in stock), but the Quadras do have some interesting options with SCSI disks. The 900 has a double SCSI bus which allows some interesting possibilities with using several disks in an array (creating one massive volume from several physical disk drives – MicroNet Technology has already announced one of these). The double SCSI chain will significantly increase the SCSI speed, but is not wide SCSI and is still limited to 7 devices in all. There is no external floppy port, so it’s a bit more difficult to replace the internal floppy with a hard drive than it is on other models. The PowerBooks have two different types of hard drives – a 17 mm high drive in the 100 and 19 mm high drives in the 140 and 170. You’re unlikely to easily increase the internal storage of a 100 particularly since the drive is soldered in. All the PowerBooks can accept external SCSI drives using a new and completely non-standard connector which you will have to buy from Apple (when they become available sometime in the future along with all the other accessories that you can’t get now) until third parties start developing them. The PowerBook 100 can be hooked to a normal Mac via the SCSI cable (to be honest, a different SCSI cable) at which point it will look like an external hard disk to the Mac. The 140 and 170 do not include this feature but Apple is likely to add it later on since they recognize that it is a good idea (apparently there just wasn’t time to fit it in). The general consensus was that the PowerBook 100 would be internally terminated since all internal hard drives are, which could cause some SCSI termination troubles if you have a strange SCSI chain. Good luck on that.

Expansion slots are the usual mess, and the Quadras include yet another type of processor-direct slot, although using it will prevent you from using one of the NuBus slots since they physically conflict. I really wish Apple would standardize the PDS slots by including a timing sensor that could figure out the speed of the processor and adjust the card accordingly, since I gather that timing is the main reason for incompatibility between the different PDS formats. The version of NuBus in the Quadras can check the timing involved, so most old NuBus cards will work in the new Quadra NuBus. However, keep in mind that the timing on the old cards will slow down the newer, faster cards, so you may not want to mix and match. The Quadra NuBus runs much faster since it has its own subsystem and doesn’t require the CPU’s attention. The figures I heard were 5 MB (don’t know the unit of time here) for the IIci versus 8 MB for the Quadras. In addition, the Quadra NuBus sports a 37 MB burst mode between cards, which would be especially useful for graphic accelerators. I said that you can use old cards in the new NuBus, but the Quadra 900 has a larger case so companies might start building slightly larger NuBus cards for the 900 that wouldn’t fit into other Macs. I’m not sure if newer cards will work in the old NuBus, and I suspect it will vary from card to card. The final feature from the Quadra is that they can support up to 14 NuBus slots using an expansion chassis such as the Expanse NB8 from Second Wave. Remember that the number of NuBus cards in operation does affect the amount of memory available, but if you can afford 14 NuBus cards you can probably afford lots of RAM.

Speaking of the Quadra case size, I’ve seen some experimental boards that require that you remove the top so there is room for the cards to spill out all over the place. Do that on a Quadra and you’ll toast the motherboard, literally. The 68040 is hot, very hot, and Apple says that you are likely to destroy the motherboard if you run the Quadra without the case for more than 20 minutes. Testing that must have been fun! Apple solves the heat problem with carefully designed airflow through the case and with heat sink fins that sit on top of the 68040 and are easily broken off. So if you muck around in your case, be very careful of those fins since your warranty won’t cover them if you break them. The corollary to the 68040 heat problem is that it will be a while before a 68040 laptop comes out, at least for use anywhere warm. It might be kind of nice to have in Minnesota – heated keyboard and all. The PowerBooks have a strange physical quirk too. If you service the PowerBooks in any way, do not test the machine until you have fully closed the case. If you test it with the case open, you could blow a fuse that is soldered onto the logic board, at which point you have to replace the logic board because the fuse is not a serviceable part at this time. Nasty! In addition, do not open or close the case when the main battery or backup batteries are in place. So to repeat myself, do not turn the PowerBook on until you have completely assembled it and closed the case. Thanks to BAKA Technical Support in Ithaca, NY for this last bit of extremely useful information.

Availability is mediocre at best. If you want a Quadra 900 or a PowerBook 100 with the external floppy, you’re in luck. Anything else and you will have to wait a few more weeks, although at least one source expected everything to be readily available within 90 days with the Quadra 700 being one of the slowest to market.

Information from:
Apple propaganda
Cary Lu
dBUG Hardware SIG members
BAKA Technical Support — [email protected]

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