Classic Mac Hardware (Troubleshooting, Upgrading, & Modifying) > General Hardware Discussions

G3 B&W!

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This is something of a continuation from:

The following (below) from :

Early "Revision 1" blue & white G3s had IDE controller problems, which made it impossible to connect two hard drives and also resulted in data transmission problems with drives containing newer controller boards. The logic boards of the "Revision 2" units have a revised IDE controller which allows two hard disks, and works correctly with newer drives, within the 28-bit LBA constraint. The Revision 2 units also contain a hard disk bracket designed for two drives and an updated graphics card.

Note: B&W G3 used here was originally a 300 MHz with Rev.1 board - recently replaced with a Rev.2 board and overclocked CPU to 400 MHz - to closely mirror Petros90’s U.K. B&W. And THIS new/used Rev.2 board has same (circa 1999) Apple part / I.D. number 820-1049-A as did the original Rev.1 board.

How can you visually differentiate between a Revision 1
and Revision 2 "Blue & White" Power Mac G3 model?

The CMD chip on Rev. 1 logic boards is PCI646U2 and on Rev. 2 logic boards is 646U2-402. To find the location of the CMD chip on the logic board, get a flashlight & shine it on the chip near the left rear of the motherboard as you face the open case. Just look for the hyphen in the number. If you have a hyphen you are on a Rev. 2 motherboard. -

*No previous adapter testing was done here with any G3 and more specifically, none with a B&W. (In the SSD adapter thread:,5436.msg39965.html?PHPSESSID=4ef84517a63f0bb481c942a9fcc8c9e1#msg39965

It all… Depends!
Note the jumper settings that work in this instance with the Seagate Barracuda (right graphic above). And then note recommended jumper setting for the Western Digital Caviar HD which suggests a single jumper placed for “Dual Master” - which does not work with the SSD+ adapter (set to slave). Instead, leaving all jumpers off (as noted for “Single, Standard Installation - left graphic) does work. Confused yet? Further testing with other conventional drives is warranted.

But this isn’t the desired two SSDs on a ribbon cable arrangement. It does allow the added performance of one SSD (for OS and apps?) plus the conventional drive (for file writes and storage?)… while also reducing the overall power demands and heat of any previous, 2 conventional HD arrangement. And REMEMBER, DieHard's got the EVB-003-02 adapters for $3.99 each!,5436.msg44513.html#msg44513 (U.S. shipping only, included.)

AND I now wonder about same arrangement for the Quicksilvers? (MDDs are still restricted to one SSD with the EVB-003-02 jumpered as Master - due to MDD’s Cable Select jumper requirement.) So, care to join in all the fun? Test your conventional drive with an SSD + EVB-003-02 adapter in a B&W… and report your findings & jumper settings.

Will eventually test here with other & larger conventional drives - but for now, this is a rock-solid enough reason to try the ultra-inexpensive EVB-003-02 / Bribge adapter with an SSD… in a G3 B&W! Hopefully, more B&W related info (and fun) to follow in this thread from: (1). Petros90’s B&W project, (2). some further details from my B&W adventure AND (3). input from other G3 B&W users here.

Ever have the notion that the B&W G3’s suffered from “Middle Child Syndrome” as they were machines “right in-between”?
[Don’t even mention a Lombard!] ::)


--- Quote ---AND I now wonder about same arrangement for the Quicksilvers? (MDDs are still restricted to one SSD with the EVB-003-02 jumpered as Master - due to MDD’s Cable Select jumper requirement.) So, care to join in all the fun? Test your conventional drive with an SSD + EVB-003-02 adapter in a B&W… and report your findings & jumper settings.
--- End quote ---

Yes, I think FBz deserves a little help here after spending countless hours on the B&W saga.  I no longer have a B&W G3 so it's up to you guys :)

Notes, Tips and Random B&W Drivel

Do yourself a favor and save time between reboots & testing.
TURN OFF Startup Memory Tests!
(Works w/ other OS 9 machines too.)

(1). Open System Folder.
(2). Open Control Panels.
(3). Hold down Command Key & Option Key when opening Memory Control Panel.
(4). When open - you’ll then see the option to turn this off at bottom of the window.

Don’t know why VM is turned on here? It’s a mystery.

Added heatsink fan for overclocked CPU.
Overclocking is easy. (Details later.)
Changed this from 300 to 400 MHz.
(*Note red arrow in 2nd pic below.)

One of these fans fits nicely atop the stock heatsink.
Don’t want to overheat that 400 MHz CPU overclock.

*Und Low Pollution!

Et Viola!

However 1st placement would not allow closing of the door.
Metal mounting chassis for CD/DVD & Zip drive in the way.

Moved the fan to the lowest position on the heatsink, now just enough to clear. Just that little bit!

Rotated the fan & added bigger screws.
Think “VOID Warranty if seal is broken”?
Again, explain later when covering the overclock.
(Sticker removed from black jumper block / red asterisk.)

Intech’s CD/DVD SpeedTools 6.0

Spent a few hours testing this and didn’t seem worth the trouble.
The stock B&W CD/DVD drives were always a bit temperamental.
Funny that both Panther & Tiger utilize the very same drive much better.
Is there another Apple CD/DVD driver for OS 9 - other than the v.1.48?

Still think that Intech’s Hard Disk SpeedTools 3.6 is very useful with the B&W / OS 9.

More to follow…

Another B&W on my doorstep yesterday.
It’s a 350 MHz and it came with an Adaptec AVA-2906 SCSI card AND a Sonnet Tempo ATA 133 PCI Host Adapter card. No hard drive(s).

I’ve never seen one of these in-the-wild. (Showing off now.)
Someone was evidently compensating for the B&W’s 100 MHz Bus Speed. And as this B&W has the original wonky Rev.1 mobo, it’s likely that the Sonnet will eventually be moved to the flagship B&W here - the one now with the most stable, Rev.2 mobo. (Ya gotta check that CMD chip.)

Call me crazy but don’t get me wrong, but it seems rather expensive and effort-wasting to boost the B&Ws up to their absolute optimum performance with processor upgrades, host adapter cards, SSDs, etcetera… when there are so many Quicksilvers (and MDDs) still “out there” that are simply faster and better equipped (out-of-the-box) for a myriad of tasks (and more cost-effective). Sure, there’s the sentimental / nostalgic angle to muscle-up these B&Ws. And I spent many years and hours fighting with mine - attempting daily graphics production… and it often did quite well. Until it froze or crashed. (OS X didn’t help.) But I still enjoy the clicky-clacky Apple Extended ADB keyboards that the B&W ADB port allows. (It’s the little things, right?) We'll see how impressive the flagship B&W performs with the Sonnet installed and overclocked to maybe 500 MHz?

Someone else (Jason Taylor) singing the praises of the B&W G3:


Well, I was waiting for Petros90 to successfully install his SSD in his B&W (or for anyone else here still running a B&W to chime in) before proceeding with this. But I need to get this all off my desktop and out of my head. Would’ve been nice to see others’ pictures of the SPEED/CTL block and how their jumpers were set… but here goes anyway.

Just to the right of the CPU, there’s that light blue block under the warranty warning. I doubt that any warranty is still in effect now 23 years later. (Some of these blocks are blue, some black and some even white.) Once removed, you can see the various jumpers placed within that block. Notice the little tab at the top of the block (top left) which serves to properly orient it when replacing it after any changes. (“Top of the block” to ya.)

Shown below, the jumper settings for the recently arrived, 350 MHz B&W. Sans warranty tape.
Intend to attempt an overclock to 450, before changing the CPU out.

Now, there are various reference sources for just what jumpers go where and for what overclocked speed. And they can be very confusing.
For instance, I thought that the red in this example below showed where jumpers should be… when in fact they denoted empty slots for the uppermost 4 positions on the jumper block. (Black being the actual jumper positions.)

The following image below “borrowed” from The House of Moth:
More detailed instructions and insights there! It’s all really quite simple.

Again, position 5 (from the top) and below, are not changed. Clock speed is set / changed only via the topmost 4 positions and the jumpers themselves need be carefully pried from the block and you might need to add some jumpers from another source to achieve overclocks. Someone mentioned that regular HD jumpers can also be used, but not likely with the plastic jumper block itself. I don’t know about this - as a “regular” HD jumper seems a bit large, even when removed from its’ plastic housing. *Refer again to The House of Moth link above.

And here’s another jumper guide, turned on its’ side:
(Notice 5-6 and 8-9 jumpers remaining all same.)

I’ve some other ZIF CPUs to test and may go as far as a 500 MHz overclock.
But even at that (if stable)… Quicksilvers will still outpace and outperform the B&W.
(Even with the Sonnet Host Adapter card and attached SSDs.)

See if I can attach that Sonnet’s Quick Start Guide .pdf below?
(Important SCSI info, firmware update mentions and other important info!)
Also available here:

So all-in-all… this has been a sort-of-fun exercise - but I’ve grown very weary of the G3’s.
AND if anyone’s interested in a B&W… looks like I may have two, to-go.
PM me.

Oi, the sentimental nostalgia of it all.

And don’t forget to add a fan! :o


I did overclock my father B&W G3 many years ago from 400 to 450. It was so cool ^^

Sorry for the "french" link but maybe this will explain some things to you on the different settings.

From 1 to 4 it sets the multiplier.
From 5 to 10 it sets the bus speed.

As you can see, by changing the bus speed you will change also the PCI bus speed so this can affect the working condition of PCI cards.


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