Power Macintosh G5

A Power Macintosh G5, released in 2003, was awaited performance improvement in PowerPC Macs. Some new technologies have been fully implemented like SATA interface for hard disks, DDR memory or faster PCI-X or AGP slots. The casing has been also redesigned, now being made of alluminum instead of plastic. The downside of this - it is very sensitive to scratches.
The first series included computers with 1.6, 1.8 and 2GHz processors, simultaneously dual-processor models have been introduced. Finally, even a dual-core, dual-processor models were available with built-in liquid cooling system.
This is unit has no PCI-X support, only 64-bit PCI cards, and its official name is Power Mac G5 Late 2004. It was a "cost reduced" unit, having mainboard design simplified and based on iMac G5. Thus, System bus was running only at 600MHz making it slower than original 1.8GHz Power Mac G5. It still supported DDR memory.

Model No: A1093

Year: 2004
Discontinued: 2005
CPU: PowerPC G5 1.8GHz
4x512MB in DDR sticks
Max. RAM: 4GB
RAM Type: DDR 400MHz (PC3200)
Hard disk: 80GB SATA
Possible to expand with another drive
Floppy drives: None
Other drives: CD-RW/DVD drive, tray-loading
Graphics: nVidia GeForce FX 5200
DVI and ADC connectors
Sound: Stereo, built-in speaker
Display: External monitor (ADC, DVI, DVI->VGA)
Dedicated OS: Mac OS X 10.3
Maximum OS: Mac OS X 10.5.8
Expansions:  - Memory by DDR DIMM
 - USB
 - FireWire
 - AirPort card
 - Bluetooth board
 - 64-bit PCI slots
 - AGP slot for video card

Peripherals in collection:
 - None

Connectors:  - USB (3 ports, one on front)
 - FireWire (2 ports, one in front)
 - Ethernet
 - Phone
 - Power
 - Speakers/Mic
 - Digital audio
 - Display connectors

This unit has been used in leasing in Germany for more than year, later it was probably imported.
To be honest, the overall performance of this unit is not much better than a bit overclocked last Power Mac G4 MDD. Selling it year after MDD was Apple's typical action towards a "budget" market in which having a Mac was more important than knowing what exactly is inside. 600MHz system bus makes it look nice in benchmarks or when it plays chess with itself, but terribly when it comes to memory-consuming or i/o-consuming tasks - just try to mess with video encoding, although I never tested the full-900MHz Power Mac I'm sure there will be at least one-quarter efficiency increase in the faster-bus one.

Hardware Disassembly Links


Memory upgrade:
Only pairs of equal-size DIMMs are supported. The first pair is in inside slots, the second goes outwards.

If starting the Mac fails, POST tries to indicate what happened by flashing its front-side LED after the first flash:
- 1 flash - error around memory, no memory detected.
- 2 flashes - 2 RAM sticks of different parameters as pair.
- 3 - Typical RAM test fail
- 4 - bad boot ROM
- 5 - CPU test failed.
Additionally if all fans spin at maximum speed, PMU (or this newer PMU replacement called SMU) may be culprit, this is unfortunately mainboard-related problem.
G5s are hot CPUs and they need good cooling. More, overclocking of G5 Macs is practically impossible as half of parameters are in mainboard and the second half in firmware. This Mac has a few fans:
- 2 fans in rear of CPU cage
- Fan on the front, facing back of PCI boards
- Fan between optical drive and hard drives cage
- 2 fans on the power supply unit, normally not seen, on the base of computer


The lever is on the rear. It goes upwards. Open cover around 10-15 degrees, slide it up. Remove the plastic part the same way or it'll break. The computer will run hotter and louder without this piece of plastic.
Now you have access to nearly everyhing except CPU covered behind its "G5" plate. Remove PCI boards if you have to, get access to one plastic bolt on the metal part, it goes from the aluminium bottom of boards cage downwards. Remove it by prying with small flat-blade screwdriver. It has a smaller bolt going into larger - you have to pull the smaller from the larger one and then remove the larger one by e.g. twisting a screw into it, but do not destroy it.
Then the CPU cover can be removed by sliding it towards front of computer and removing/opening. This component is necessary for proper operation of cooling system, without it's noisy, as well as without this plastic part with square hole.
Now look carefully on capacitors. Are they OK? Yes, some of these units had capacitor disease.
These Macs have no internal reset button - the power unit resets when the unit is unplugged for a minute. Earlier had one behind the fans, look at the bottom of mainboard.
Hard disks can be removed by rotating the lock on the right side of disk, disconnecting SATA/power cables and sliding them out. First, it looks like the upper one won't go out, but it is on small ramps which lead it lower.


https://everymac.com/systems/apple/powermac_g5/specs/powermac_g5_1.8_2.html - Specification,
http://powermac-g5.com/bobsg5tips.html - G5 modern usage tips