Is my Apple PowerMac G5 compatible with my PCI-based PowerCore?

Yes, but there are some considerations. There are three types of expansion slot types in the Apple PowerMac G5 models: PCI, PCI-X and PCI Express. Please see below for compatibility information on each.

If you are not sure which type of expansion slots you have in your G5 model, please refer to the documentation provided with the G5 or the Apple Support website.

PCI:

If you wish to use only 1 DSP card, all PCI based based PowerCores are compatible with PowerMac G5s with PCI slots.

If you wish to use more than 1 DSP card, we can at the present time not recommend using the PowerCore Element/PowerCore PCI with the:

Single 1.8 GHz G5 with PCI-slots (September 2004 low-end model)
Dual 1.8 GHz G5 with PCI-slots (June 2004 low-end model)
Dual 2.0 GHz G5 with PCI-slots (April 2005 low-end model)

With more than 1 DSP card in the machine (either a 2nd PowerCore or a Universal Audio UAD-1 card) PowerCore is not initialised correctly during boot-up. We have checked into this issue and are unfortunately not able to offer a solution via a software update, as this issue is directly related to the hardware architecture of the G5.

So if you wish to use 2 DSP cards, we therefore recommend you go for one of the other PowerMac G5 models instead. If you already have one of the G5s mentioned above, you should consider a FireWire-based PowerCore like a PowerCore Compact or PowerCore FireWire or upgrading to a PowerCore PCI mk II.
Multiple PowerCore PCI mk IIs run successfully with the Dual 1.8 GHz G5 with PCI-slots (June 2004 low-end model)

PCI-X:

According to the PCI-Sig, the group responsible for creating and maintaining the PCI specification, PCI-X is 100% compatible with existing PCI cards as long as the PCI card meets PCI 2.1 or later. PowerCore PCI meets this requirement.

In the Apple PowerMac G5 desktops that we have tested, we have been able to run multiple PowerCore Element / PCI / PCI mkII / Unplugged cards in the PCI-X slots.

PCI Express:

PCI Express is an entirely new bus architecture previously known by the name “3GIO.” Until the launch of the October 2005 Dual Core PowerMac G5 models, only PCs had been equipped with PCI Express slots.

Furthermore PCI Express uses a different type of connector than PCI and PCI-X. The two are not compatible, which means that the PowerCore Element / PCI / PCI mkII / Unplugged are incompatible with the October 2005 Dual Core PowerMac G5 models.

The only type of PCI-based PowerCore compatible with PCIe (PCI Express), is the PowerCore Express.

Both the PowerCore Compact and PowerCore FireWire are compatible with the October 2005 Dual Core PowerMac G5 models.

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