CF As A HD

[Elfen]

This comment in the Q630 PATA thread and past threads on the forum made me think...

Floofies, on 15 Jan 2016 - 2:34 PM, said:

I think CF is a whole other can of worms, but it's related to a bigger problem with the onboard ATA controller.

Thus I am creating this this.

Many of us here have used Compact Flash (aka CF) and other forms of Solid State Drives (aka SSD) as storage media for our hard drive replacement needs with varying degree of success and satisfaction. So I am drawing on my personal experience (mostly) and what is stated on Wikipedia Compact Flash article (for fact pointing).

Here are the basic facts:

Compact Flash cards were first developed and made by SanDisk Corporation in 1994 using their Flash Memory Technology. They had licensed their Flash Memory technologies and their Compact Flash standards to other companies.

Compact Flash has a 50 pin female connector, which can be used on a PCMCIA slot with a passive adapter (no electronics, just wires coming from the PCMCIA straight to the CF). This means that the Compact Flash card can be used as a memory device or as a IDE Storage device; this depends on the OS of the host machine, the Compact Flash's controller and "state of mode" pin on the PCMCIA connecting to the Compact flash (See wikipedia article) . Since nearly all Compact Flash controllers after 2005 are made for IDE, CF cards after 2005 will act like hard drives inside a host system.

In IDE Mode (from the "state of mode" pin" on the CF/PCMCIA Connector) the Compact Flash defines its interface smaller but electrically identical the ATA interface. This makes the CF a hard drive that uses Flash Memory as a storage media instead of mechanically spinning magnetic platters.

In that a Compact Flash by definition is a "Hard Drive" as per the computer's hardware and OS recognition of the device. However there are some OS that takes the CF's device Identification bytes and refuses to recognize it as a hard drive but as a "removable media" and will refuse to boot from it without problems.  Most noticeably- Microsoft Windows XP and Vista. There are some some tools out there that will change a CF's Identification Bytes into a Solid State Drive's Identification Bytes and make it acceptable by OS as a standard storage and bootable device.

A Compact Flash's life span is about 10 years, the same as a hard drive. This depends on many factors like how often it is used, its operating environment, how many write cycles it has, how big it's flash memory core it, how it this memory core partitioned, does it have "wear-leveling", and so on. When a Compact Flash reaches its end of life cycle, it becomes a ROM, like a CD/DVD. But many CFs tend to drop dead with total data failure. That is because of its operating environment, and either a power surge or static electricity pulse killed it and not because it reached it end of life cycle. CFs are electronically sensitive devices and are more prone to failure due to power surges or static shock than a hard drive of the same capacity.

Do note that there are hard drives out there that are over 10 years old (some even 20 years old and older) that are still working today. The same with CF cards in that there are many units out there that over surpassed their expected lifespan by several years and are still going strong. With hard drives, its the mechanics of the device that keeps it going. With the CF, it is the writing to the device that shaves slices out of its life span. One can only read from the device indefinitely if so they want. But if you do a lot of writing of files or use the CF as "Virtual Memory" then you are taking away from its lifespan. In use on a Computer's OS, you need to turn off Virtual Memory, (most) System Caching and System Logging to get the maximum lifespan out of a CF.

For us Mac Owners, up to OS 9.2 there is little or no System Logging from the OS. There is some form of logging from applications like MS Office. It is in OSX where there is a lot  System Logging one needs to be aware off and if possible turn them off for a personal system (but needed on a server system). But disk caching and virtual memory should be turned off or set to a minimum level on Pre-OSX Mac Systems.

Because CFs (and all other forms of SSDs) are solid state storage devices, they are a lot faster than conventional hard drives. This is because there are no mechanical movements to be made, signals to convert and buffers to fill in a solid state device as in a hard drive.

My next post will be of my personal experience in using CFs and comparing them to other SSDs and actual hard drives.

 

[Elfen]

Some simple math...

Flash Memory cells can take a million or more write cycles before it fails into a ROM-like state. Depending on how often this is done to a memory cell, it can take months or years to achieve a million write cycles. Thus if you are writing to the same area on the Flash Memory, that area will wear out faster than the rest. With wear leveling, the Flash memory controller will spread this write out to a larger area and slow down the progression of the wear.

In a 1GB Compact Flash card, this can take 5 year to do if the system is on 24 hours and constantly writing to the CF card. In theory you can write to the CF Card 10,000 within that 24 hours, and within 1000 days (a bit more than 3 years) you will start to lose the CF's capacity. Conversely if you hardly write to the CF Card, you can write to it for a much longer amount of time.

This is why it is important to turn off Virtual Memory, System Caching and System Logging, or you can install a second CF Flash into the system and use that as for system caching/logging and virtual memory.

Do note that Higher Capacity CF cards (and SSDs in general) and "Industrial" and "Military" grade CF Cards do have much higher write cycles than low capacity and "standard" grade cards. In the case of "Industrial" and "Military" grade cards are more robust than standard grade cards and can take on harsher environments, power surges and static shock better than standard grade cards but at the expensive of read/write speed access. Though this slower speed will be unnoticeable to you, it is there and is something to consider if you are making a high speed system.

 

[Elfen]

Personal experience with CFs and SSDs

I have been using CFs and SSDs since around 1999 and earlier if you count FLASH RAM PCMCIA Cards. I have very few failures with them but some of the failures were catastrophic (with total data loss). Like I stated before in the first post, CFs are delicate and prone to failure if treated badly.

At least 1/2 of my computers - both PC and Macs - have a SSD in one form or another in it and about 3/4 of them have a CF being used as the SSD. Once I figured out what was causing failure  on those systems that did failed, it was easy to overcome and not let it happen again. 1) static electricity and 2) power surges were the culprits in my CF and SSD failures. Once I figured that out, I have been problem free.

Yes, using a CF as an SSD is fast, faster than a hard drive and in some cases twice or four-times faster. But expecting things to be fast should be the last of one's concern. One's first concern is to get it working.

The easiest way to get this working on a Mac laptop is to make sure that the laptop has an IDE port on it and to get a CF to IDE adapter if you are using a CF; most IDE/ATA SSDs comes in 2.5in format. The PowerBook 150 and 190 are the only 68K PowerBooks with IDE instead of SCSI. All other Powerbooks up to the Intel MacBooks use IDE as their hard drive interface. For this to work on a Mac Powerbook with the IDE interface you will need a Single CF to IDE adapter and not a Dual CF to IDE Adapter. Then you put it in the Powerbook like you would a hard drive, partition it, format it and install a system on it.

Conversely if your Powerbook has a PCMCIA, you can get a CF to PCMCIA adapter and use it like one would use a USB Thumb Drive that can boot from the PCMCIA Port. You would need to partition it, format it and install the system on it. This will will for any Powerbook with a PCMCIA except for the Powerbook 500 series. In the Powerbook 500 series, it can see, recognize, format and use a CF mounted volume(s) through the PCMCIA but it wont be able to boot from it because the PowerBook 500 series is missing the Boot ROM for the PCMCIA.

"But I own a Desktop!"

"But my system uses SCSI!"

"But my system uses SATA!"

"Will it work for me?"

"How much is this going to cost?"

And? My personal experience is that it should. Just like with laptops that have IDE, a Mac Desktop with IDE will with with the appropriate CF Adapter. You will also need a power adapter cable for PC Floppy Drive to connect the CF Adapter to give it power because it uses a small power connector. This work fine on my PCs I have set up. It also works on my Perfoma/PowerMac 6213CD as it uses a IDE port.

I have also used a CF-to-SATA Adapter in an XServe G5 and it worked well on it. Now - I have not tried the CF-to-SCSI but I keep hearing from many forum members out there claim that the Aztec Monster CF-to-SCSI adapter works great on both Mac desktops and laptops. I would have to side with them. The only issue here is getting the right one for your system - desktop or laptop.

Rules to abide by:

1) When getting a CF-to-IDE adapter for the Macintosh, get the Single CF to IDE Adapter. Dual CF to IDE Adapter do not work on Macs, you turn on the Mac and get a grey screen as the Mac will be stuck looking for a drive that it can not see.

2) When using the CF-to-IDE adapter, have the Master/Slave jumper to Master. Otherwise the Mac will not see your CF as a drive. This also applies to IDE/ATA SSDs.

3) For System 6 and 7, keep your partitions 2GB or less in size. For OS 8 and 9, keep your partitions 4GB or less. Having larger partitions will confuse the system.

4) If you have a CF or SSD that is larger than the largest allowable partition, you need to partition and format the remaining space into smaller drives. The example I use for a 4GB CF/SSD on System 7 is:

1st Partition - 500MB for Boot and System files

2nd Partition - 1GB Applications

3rd Partition - 1GB Working files & Personal files

4th Partition - 1.GB Multi-Media Files, Downloads, etc.

5) Do not expect the system to speed up, though access to files and system processes will be faster in using a CF or SSD. It is only the access - the reading and writing - that is speeded up. That reflects in the system running faster and everything else working faster. But you are still on a Mac IIcx running a 16MHz '030, your system is not going to turn into a Quadra 950 because you put in a CF/SSD into it.

Next post - Problems and issues.

 

[Bunsen]

Moved to Peripherals.

 

[Cory5412]

I suspect this is being made out to be more complicated than it really is. It's not hard to find out what works, and we could/should hypothetically be using the wiki to document what doesn't when we find it. The real problem is when we ignore solutions that are known to work in order to try to find something that's cheaper.

Also, can we please stop with shenanigans about partition sizes? It's knowable for any given system and OS version what the limits are.

Some personal/anecdotal thoughts:

I've got a 32 gig CF card in a laptop IDE adapter connected to a hard disk controller for the Apple IIgs from the '90s and everything's working perfectly. It's a little hilarious because ProDOS partitions are limited to 32 megs apiece.

I can't think of any reasons why this type of adapter wouldn't work well in an IDE Mac as well.

For Mac OS 9 and earlier, if you have enough RAM not to hit swap, I don't think you're going to have any issues with wear, but it's a good idea to have backups available just in case.

I've also used CF cards in PCMCIA adapters on a 1400 and on a 3400. I was able to boot the 3400 from a then-modern CF card in the 3400, and I was able to use a CF card in a 1400 for data transfer. I don't believe I've yet tried booting my 1400 from PCMCIA. My 1400 does have a 30 gig IDE disk in it. (10 gig system 7.6.1 partition, 20 gig system 8.6 partition.) There's no reason why the same type of CF adapter I'm using in my IIgs wouldn't work well as a replacement.

I think the real key here is finding adapters that work well -- on the "desktop" side of things (Macs like the 580/630 and 5000/6000 series Performas) is where you're going to run into the most problems.

For SCSI Macs, it's pretty straightforward: Get either a scsi2sd or an aztecmonster, and you'll be happy.

Another thing to consider for PCI Macs is that System 7.6 can run 2TB disks perfectly well using PCI SATA cards, so there's little incentive to use CF for that kind of system, especially given that with that class of hardware, you're more likely to be in a situation where you'll want or be able to run more programs than you have memory. Modern SATA SSDs basically don't have reliability problems though, even if youh're running without TRIM (which you will be on an old Mac), should you decide to use an SSD with your SATA card.

 

[Elfen]

Those are some excellent points, Cory5412.

For me its a cost incentive issue and speed though the latter is not really an option but a positive more for it. Being on disability and not working means that my income is limited by what Government Insurance gives me every month. So for under $50 one can get a PATA/IDE SSD or a CF with an IDE adapter of up to 32GB. But the Mac 68K Software library is only about.... Hmmmm... 12GB as a "from top of the head" figure. With personal files and what ever, one is going to have a difficult time filling that up. But 2TB? I can see that on a current model Mac but not a IIci, Q950, PM5600, PM9600, or anything before a G3 Mac.

Thus with old hard drives failing, how is one going to keep their systems running? NOS (New Old Stock) can arrive dead from the same issues the original drive died from. The only thing left is a Solid State Drive system - whether it is a CF on an adapter or an actual SSD.

But there are some issues with that. Not all CFs, SSDs or their adapters work on an old Mac. For me, I'm one of the lucky ones having been through the bleeding edge and found out that works and what does not work for a given price. And I have shared my information with other forum members to help them out. Just recently, one member tried out a "Syba-USA" (aka Syba) adapter for his CF and Performa 630CD and it is not working for him. I gave him some pointers to help out, but still it is not working. I scrounged the forum and found 2 other threads where forum members tried the Syba Adapter and it did not work for them. I pointed this out to this forum member and advised that he should try another adapter and I recommended the ones I use (from Chinese sellers in ebay). We discussed the finer technical points like access UDMA in this discussion, which the Syba adapter claims it has.

https://68kmla.org/forums/index.php?/topic/26818-ide-2-compact-flash-formattinginitialization-issues

When it comes to certain solutions, it is "Buyer Beware" out there, especially with hard drive replacements for old Macs and using solid state storage systems as a possible solution.

Forum members should read this and then put in their experiences to they can contrast and compare notes. That is why I started this.

 

[Bunsen]

One thing to note is that the Powerbook 150 appears not to play nice with CF cards as boot disks.  There is a workaround in that article, but it's not simple.

 

After some head-scratching, I came up with the circuit shown in the diagram below. It "snoops" on the IDE bus, waiting for the host to issue an Identify Device command. When that happens, it modifies the first word of data sent back to the host from the device, changing bit 15 from 1 to 0. Then it goes back to sleep and leaves everything else alone.

 

[Elfen]

I remember that article, Bunsen! Thanks for bringing it up!

 

[Elfen]

Problems (I have experienced and solved):

Despite all the past discussions about HSF ad HSF+ Format and Partition/Hard Drive  sizes, there is a problem here. As argued in other forum flaming threads, HSF and HSF+ can (In Theory and according to some- in practice) go past 16GB and even towards the Tetrabyte Range. Whoopie Doo!

But that does not solve the problem, as it turns out was a system & software problem. System 6 and System 7 can not see a Partition/Hard Drive partition larger than 2GB without problems. OS 8 and OS 9 under HSF+ can not see Partition and Hard drive sizes larger than 4GB. For me this has been a stumbling block because in some systems I use 16GB SSD and CF-SSDs.

I accept this as a fact - Partition/Hard Drive sizes on PreOSX machines should not exceed 4GB for OS 8 & 9 and 2GB for System 6 & 7. But here there is a tiny problem with some...

SanDisk CF are a bit larger than 2048MB (2.0GB). They are 2100MB (2.1GB), though they are labeled as 2.0GB. This is great because you are getting a bit more space with SanDisk CFs (as well as their SSDs). Many other Flash Memory makers design to be as stated - a 2GB sized unit is 2048MB. The problem here is when you partition and format the SanDisk unit fully and it fails (gives errors on System 6 or 7 under HSF.)

The solution is to partition the SanDisk CF/SSD as 2048MB or less and then a 52MB (or so - the remainder of the CF/SSD) and then format them accordingly. Then it will work.

You can check this with a PC by putting the CF/SSD into the PC and go to its BIOS and look at the Drive Size\Geometry of the CF/SSD. It will tell you exactly how big your CF/SSD it. If it is 2048MB (for System 6/7; 4096MB for OS8/9) you can partition it and format it.

According to TechKnight, you should partition it to less than 2GB in order for the unit to conduct EEC and Wearleveling. So instead of 2GB, it should be 1.9GB or less, I'm guessing about 1% to 5% of space should be free for this. But I have not done this personally and not had any problems. Maybe I'm lucky in that as I have SSDs and CF-SSDs on systems over 10 years old; since 1998; and they are still running as new.

Another problem was a physical problem with the adapters not fitting on the connector with some laptops, particularly Mac Laptops (and a couple PC laptops as well as I seen). This is because the ribbon connector on the laptop has a plug in it, similar full size drives and connectors. On most laptop hard drives, there is a pin missing to correspond to the ribbon connector (Pin #20). But on CF-to-ATA/IDE adapters the pin is there. To solve this, you need to bend or cut the pin. See the diagram:

Pin 20 is the pin you need to cut for it to fit the Mac ribbon connector. Lately some Chinese sellers on Ebay has been selling these adapters with Pin #20 already cut off so you wont have to do it yourself.

A third problem is Dual CF vs. Single CF to ATA/IDE adapter. In my research, Dual CF Adapters do not work on Macs laptops and desktops. I have repeated this experiment on every system I have with Single and Dual CF Adapters, and Dual CF adapters never worked even it has a single CF on it. Turn on your Mac, and it would to RAM Test, and stay there at the end of the RAM test with nothing but a grey screen. I have left systems on for a 1/2 hour to see if I would get a floppy disk icon and still nothing. This is true for every system I tried from the PowerBook 190 to the PowerBook G4 and a few desktops with IDE/ATA. With a Single CF Adapter, the Macs works fine! But not Duals.

Problem 3b I have seen happen repeatedly on the forum and it is similar my third problem. The Syba or SybaUSA does not work on Macs for some reason despite being a single CF adapter. I use the cheap adapters from ebay that costs less than $3 a shot; similar to the one pictured above. Out of the dozens of adapters that I have bought over time and used, only two the them were bad. Anybody wanting to use a CF as a hard drive, I recommend you use these cheap CF-to-ATA/IDE adapter.

This is the Syba (SybaUSA) CF Adapter. Avoid them!

On the old "Booting From A CF Thread" we discussed UDMA access and how to make things work faster on the older Macs. In truth, UDMA does not wok on the older Macs because it is not supported. UDMA does work on G3/G4 systems but not before, and even then, it is for systems of 2005 and after, so Wallstreet to Prismo G3 UDMA may not work. But in most cases, these cheap Ebay Adapters wont support UDMA either because of 2 missing wires. See:

http://support.fccps.cz/download/adv/frr/cf.html

You can solder two wires and get UDMA if it is supported on your system or leave them out and enjoy on your Non-UDMA Supporting System. 30mb/sec is still fast (top speed of Non-DMA Accesss), faster than most hard drives and the SSD/CF-SSD can easily reach these speeds if it supports it. Anything that is 200X Speed or faster will obtain the 30mb/sec speed.

On post #34 on the same thread, I have my 1400c/166 booting from a 8GB CF. There is no magic going on. It's OS8 so the partitions are divided up into 4GB and 2 - 2GB slices. It is fast and quiet.

Other issues and solutions to come. But do post your issues, problems and findings. This is not about me. I'm just sharing what I know.

 

[TimHD]

Elfen

Thanks for the great summary post (Bunsen, can that single post go up as a sticky somewhere, or cut'n'paste and moved to top of a new thread?)

Separately, I am having a weird issue where I can boot an AztecMonster SCSI-CF with 1GB compact flash (so no 2gb issues here!) in my external HDD bay (old 80SC) as ID=0 (with no other SCSI devices in/attached to the SE/30) and transferred and ran files from it, but when I moved it inside my SE/30, it won't boot from it, let alone recognise it when I boot with floppy! I have formatted and tried 'updating' the driver with Lido etc, but no luck. ARTEMIS' manuals are a little sketchy, so have tried numerous jumper combinations re: Termination etc on the board, but no luck. 

 

[Paralel]

I have a Sandisk 4 GB that I used and I didn't have any trouble with the partition sizes. It made two 2 GB partitions no problem.

Strange that their 2GB cards are problematic.

 

[Cory5412]

Ultimately, this needs to be put in a wiki article, but we really need for the correct information to be saved, which not everything here so far is.

For example, Apple directly sold Macs that boot OS 9 with 120 gig hard disks in them, and Macs that boot OS 8 with up to about ten gig or so hard disks. There's nothing stopping system 7.6 from using a 2TB partition.

It's documented on Apple's site that there may be problems in 7.5.2 and earlier with larger-than-2-gig partitions, but I haven't really seen it substantiated anywhere else.

 

[Elfen]

It's documented on Apple's site that there may be problems in 7.5.2 and earlier with larger-than-2-gig partitions, but I haven't really seen it substantiated anywhere else.

I Love the wording of "MAY."

My experience is in using a A PowerBook 190, 5300, 1400 and a PowerPC 6312CD, all IDE/ATA Machines, I had problems with formatted partitions larger than 2GB on a CF on System 7.5.5 and System 7.6.1. Problems included - improper partition size reporting, and files not being able to be written to the formatted partition.

I understand that HFS and HFS+ can handle Tetrabyte ranges of hard drive space, but the OS itself does not go that high as I see it. Even on my 1400 with the 8GB CF-SSD on OS8, I had to divide it up into 3 partitions of 4GB, 2GB and 2GB. The first 4GB Partition is for the OS and applications, and the other 2 - 2GB Partitions are for work, media on one and backup of the Boot system on the other.

Now under OSX - I can use anything from 16GB and up on a G3/G4 iBook and PowerBook. But this is not about OSX though G3s are discussed (like the 2 Wallstreet G3 I have, one with a 8GB CF as an SSD and the other a 8GB KingSpec PATA II SSD. They run at about the same speed in boot, application/data access and shutdown times.)

 

[Elfen]

Problems with CF-SSD and WallStreet G3s:

When partitioned correctly, they work like a dream in the G3s series PowerBooks. The problem is in the hardware mounting.

The hard drive in the WallStreet, Lombard and Pismo G3s is mounted upside down and wedged/friction held by the hard drive caddy and the CPU Heatsink. Gravity and the weight of the hard drive, the keyboard and 2 heatsink screws literally holds it in place. One good whack will loosen it and it will disconnect from the logic board; it has happened.

The hard drive screws onto the hard drive caddy with 2 or 4 screws, depending on how many were used and if the screw holes lined up with the caddy. And then the hard drive connects to a tiny edge board that screws onto the back of the caddy and goes into the logic board. But the single CF IDE/ATA Adapter has no screw mounting holes and you can put the adapter onto the edge connector and plug into the G3 Logic board, but it will work itself loose and disconnect.

With foam padded double sided tape you can line things up with the CF adapter board to the hard drove caddy and then put a piece of foam double sided tale inside the caddy, connect the edge connector to the CF Adapter, line things up and press the adapter against the double sided tape. Then screw down the edge connector to the hard drive caddy and then put the whole thing in where it belongs inside the G3 and make sure the edge connector goes into the logic board slot. Once everything is secure in place, it should be able to boot. If it blank, you should be able to partition and format it before installing a system on it. Apple HD Setup may not be able to recognize it, but other third party hard drive partition formatting software will.

 

[Elfen]

I have a Sandisk 4 GB that I used and I didn't have any trouble with the partition sizes. It made two 2 GB partitions no problem.

Strange that their 2GB cards are problematic.

It is strange that they give a tiny bit more = 2100MB (2.1GB) instead of 2048GB (2.0GB). Maybe its a marketing ploy or a plus on their part. No other 2.0GB CF I seen this geometry, only on the SanDisks. But it is only a problem if you try to use it the whole 2.1GB. It's fine if you partition it as 2GB and have some 50MB left over.

 

[Elfen]

Separately, I am having a weird issue where I can boot an AztecMonster SCSI-CF with 1GB compact flash (so no 2gb issues here!) in my external HDD bay (old 80SC) as ID=0 (with no other SCSI devices in/attached to the SE/30) and transferred and ran files from it, but when I moved it inside my SE/30, it won't boot from it, let alone recognise it when I boot with floppy! I have formatted and tried 'updating' the driver with Lido etc, but no luck. ARTEMIS' manuals are a little sketchy, so have tried numerous jumper combinations re: Termination etc on the board, but no luck. 

I have not tried this on a Aztec Monster.of anything smaller than an 040 CPU. But I do know of a few who have got it working on a Color Classic II (LC III class machine). I need to find a few Aztecs for my CF / Old Mac use.

The issue I might see is that the Mac II Series (which includes the SE\30) and LC Series does not boot from CD or other removable media. On the PC-XP OS side of the Computer Universe, CFs are not always recognized as 'hard drive media' but many times are recognized as "removable media." This is because of a hardware identification bit in its media. There used to be a SanDisk and/or HP Media identity bit modifier program that can change the CF identity bit into a hard drive identity bit. Though I do not know it will help with the SE\30 and other Mac II/LCs, it does help with the PC side. Some where I have that program and will look for it. I'll post it up when I find it.

In the least, the Aztec should have termination on and any SCSI ID of 0 - 6 (#7 is the Mac), preferably 0. Any external devices must also be terminated.

Question: What system are you trying to boot on the SE\30 on the CF?

 

[TimHD]

Question: What system are you trying to boot on the SE\30 on the CF?

Tried on 7.5.5 SE/30 and a SE/30 7.1.2. Given all the options I have tried re: ID and termination, I am leaning towards this being something that just doesn't boot from an SE/30.

Though even if it is seen as removable media, why does the CF card as ID=0 boot ok when it's in an ext (old 80sC) case, but not when it's inside the SE/30?

 

[Elfen]

Ooooo...!

It boots externally and not internally?

That can be the Bournes filter going bad, or a bad SCSI Cable or cable header ends. Replace the internal SCSI cable and see if that helps. And see if the CF Boots on the SE (even if it crashes on boot).

It can also be a loose or broken SCSI Connector on the board but that's rare.
 

It is tiny clues like this that helps out a lot in figuring things out.

 

[Paralel]

I have a Powerbook 540c (with a 550c processor daughterboard) running the aforementioned 4 GB Sandisk CF using the Adtron CF2SCSI board without trouble on 7.1.2. I think Apple's caution is unwarranted.