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Duo FPU Modification

As of January 1999, this modification is still available at US $349, however your money is likely better spent on a used 270 or PPC Duo.

Apple PowerBook Duo computers with 68030 processor show an impressive performance boost when a math coprocessor (otherwise known as a Floating Point Unit) is installed. Performance in mathematics intensive software can be as much as 10 times greater with an FPU, but the improvement depends strongly on the software itself. An FPU contributes so much to math performance that some math intensive software will not run without an FPU as it would simply be too slow.

Duo 210, 230, and 250 users can use an FPU installed in the Duo Dock, but for portable FPU performance, there are only two options:

1. Use a different PowerBook

2. Have an FPU custom installed for you

We will install a standard Motorola 33 MHz 68882 in a mini or micro-dock that you supply, or if you prefer, inside your Duo itself. The FPU used is the same as the one used in the Duo Dock, and requires no additional software (support for the FPU is already built into the Duo System Software) for complete compatibility.

The FPU installation is US $349 including return shipping via UPS air in Canada or USA. If you supply the appropriate FPU, we deduct $85. (The FPU used is the MC68882FN33, as used in the Duo Dock)

• The installation takes two weeks (typical) for installation in a Duo, Apple Floppy Adapter, Apple MiniDock, or Newer Technology SCSI MicroDock or Ethernet MicroDock.

• If you wish installation in another Duo product that we have not yet investigated, you should allow an extra week for a more complete check and evaluation. In this case, if we decide that we cannot perform the modification reliably, we will return the unit and refund your shipping expenses (within reason).

• Payment is by cash equivalent (money order, cashier's cheque) in advance, or by Visa/MasterCard billed when your unit is return shipped.

• The modification does void any remaining warranty on your unit, and will probably prevent any Apple Service technician from working on it (other than installation of Duo RAM or Hard Disk). Installation in a Duo includes free removal of the modification should your unit require service from Apple, or if you wish to upgrade your Duo in the future. Although removal of the FPU from the Duo will leave very little evidence, we cannot guarantee that a warranty repair will be allowed.

• We do warrant our modification against defects in materials and workmanship for 6 months.

• The internal Duo modification includes circuitry that senses whether another FPU is present, and disables the internal FPU accordingly to prevent contention. The internal mod also includes a power control circuit that turns off the power to the FPU when the CPU cycles down to the nap/idle state. In all, the FPU increases motherboard power consumption about 10%, which is barely noticeable if the hard disk is used to any significant extent.

• If you are familiar with surface mount digital circuits, you may be interested to know that Apple has not provided a place in the Duo for an FPU, and in fact there is not even enough room to install a PLCC socket for the FPU; as a result the modification involves hand-wiring the FPU to the motherboard, which is delicate and time consuming.

• We will attempt to accommodate special requests, such as a 40 MHz FPU for use with modified Duos.

• The 68882 FPU is only used by those Duos having a 68030 processor. If your Duo has a 68LC040 processor, it will not use the additional FPU. This limits the modification to the Duo 210, 230, and 250 models.

Ordering Procedure

We request that people make a reservation for a particular week so that we can schedule our efforts and make sure we have the necessary parts on hand.

After checking with us for a reservation, you may send your unit for modification via UPS or insured mail. UPS express is typically 2-3 working days, Air Mail is typically 1-3 weeks.

Do pack your unit well; two inches of packing material on all sides is recommended, and you should pack the electronics in an anti-static bag to keep the packing material out of the connectors.

If you ship via UPS, make sure our phone number (and yours) is clearly marked on the shipping label. UPS likes to have 5 copies of a (simulated) 'commercial invoice' which identifies the shipper (you) and consignee (us) as well as describing the contents and its value, again phone numbers are important to make sure the process is speedy. You put this in an envelope on the outside of the box. If you wish to pay by MasterCard or Visa, you will need to provide your card number, expiration date, mailing address, and phone number. The actual billing is done by Dafax Processing Corp. in NY when we return ship your unit, so they will send you confirmation for your records and your statement will show Dafax as the billing source. NY state residents add NY sales tax for credit card billing. Please send confirming email when you ship your unit so that we can watch for it. Also, if you send UPS, tell us the tracking number and the date shipped so that we can make sure UPS stays on their toes.

Thank you for your interest, for further inquiries on this product, contact:

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