First Powermac G5 (Late 2005) Project - Design According to Ive

[kiwisincebirth]

Motherboard Tray

I only had three motherboard standoffs available to use, as four had been left in the case to hold the mid-frame (PCI CPU divider). So had to get new standoffs.

Many projects went with the approach of gluing standoffs directly to the case, and either attaching a MB tray, or MB directly to these standoffs. For some reason I didn't like this approach, but instead decided to emulate the apple design.

I used a sheet of aluminum, held against case with existing case nuts and screws. These are the ones that held the CPU mounting frame to the case. And mounting the standoffs directly to the aluminum sheet. This approach means, there is no gluing to the actual case, and it gives you the flexibility to replace the tray at any time.

I measured the MB standoffs I had removed they appeared the be 13-14 mm in height, so I purchased 12mm standoffs and an aluminum sheet of 1.5 mm in thickness. The dimensions of the sheet were 34x29cm which easily accommodated a full 30x24cm ATX motherboard. I kept the extra size because it gave me the chance to mount other things to it latter.

I did have to cut a corner of it out, to have space for the optical drive tray mounting holes. To build the tray basically was in two parts, mounting the aluminum sheet to the case, then mounting the standoffs to the aluminum sheet.

First it involved measuring the case standoffs and drill holds in the aluminum sheet. The existing CPU frame, that was screwed into the mounts, acted as a template for many of the holes. Once all the holes were drilled, the aluminum sheet could be screwed to the frame. Note: many of the holes I drilled had to be widened, because I was not very accurate with a ruler, pen, and hand drill.

Next was the mounting of the standoffs, this was a very similar process to measure and drill holes. I used countersunk screws from underneath, to hold the standoffs to the tray. I used locktite the help held the standoffs in place and tightened the screws fairly tightly. There are exact specifications for ATX hole placement, so was able to do a better job of alignment.

Last I sanded the plate back a little bit (to give it a brushed look), I should have done this before I put in the standoffs , but mostly this wont bee seen anyway. You can see the results below.

 

[Fwiler]

I can't wait to see the connections you made for the power switch and led.
I've been going around everywhere looking for the correct pin out but it doesn't seem to match what I've found so far.
Mine looks exactly like yours.

 

[kiwisincebirth]

I've been going around everywhere looking for the correct pin out but it doesn't seem to match what I've found so far.

I hate to disappoint but my approach didn't involve the connector so don't know the pinouts. If you are interested the pinouts try these threads.

http://www.insanelymac.com/forum/index.php?showtopic=88856
http://www.insanelymac.com/forum/index.php?showtopic=258071

I actually soldered small wires directly to the components (power switch and LED). I haven't document this yet but do have a couple of pictures which may explain it

 

[kiwisincebirth]

Motherboard IO Ports

Credit to the following post
http://www.insanelymac.com/forum/index.php?showtopic=274997

This is one of the last major parts of the metal work that I did. After many hours of modding I though I would be better at using new tools (dremel) and less likely to stuff it up.

Most of the mods I have read fall into one of three categories

• The mod covers the back entirely, usually with a mountain mods back plate, while this gives a very functional system, to me it compromises the rear appearance too much.
• The mod go to extreme lengths to keep the existing ports using extension cables to connect the MB to these ports, to me this compromises the internals of the case too much, for the sake of the exterior.
• The mod totally rebuilds the back of the case, using skills similar to panel beating to move the fan ports, provide a modern set of ports, but the bogging, painting etc make it look like it came from the apple factory. I simply don't have the skills to do this, but to me is the best approach.

My approach is simply to cut away the existing holes, creating one large port to access the motherboard connectors, while leaving the existing fan ports in-place. The advantage is that this is the minimal amount of rework to the back to create a functional system, so looks very similar.

The disadvantage is primarily that not all the ports are accessible, the sound ports are not directly accessible, however because the MB is set back from case there is room to get to the ports. I used a right angle extension cable. And I lost complete access to the optical audio port

My technique was to cut draw lines on the outside of case, with a perminant marker (still haven't got it all off), and cut inside the line leaving a small gap. Once cut out, I then set the dermal down to a slower speed, and used the cutting tool to slowly grind up to the edge of the line. Finally I used small hand files, to smooth out and make a straight line, and clean the edges and corners

I left the left most two USB, intact, they didn't need to be cut, and could possibly use these in the future.

I was pleased with the outcome of the cutting.

 

[chaosdesigns]

Nice work! This is the way my son envisioned his G5 mod. A product called "Goof Off" removes permanent marker with one wipe. Just google it.

 

[kiwisincebirth]

Nice work! This is the way my son envisioned his G5 mod.

Thanks I still have a way to go, hopefully the end result is worth it.

Hard Disk Drive Hot Swap Enclosure

I intend to use the existing Apple drive bay, but I need capacity for more than two drives, and if I went to a ATX Motherboard would have to remove the apple drive bays altogether. I had to decide how and where to mount the drives, there is one obvious place, which is at the bottom front of the G5 case.

The CPU fan mount in the late 2005 is quite wide, but its design is quite easy to modify without comprising its function. The fans can be mounted on the right hand side (in the same holes) leaving a large overhanging piece of plastic which can easily be removed. Once removed there is space for 3.5" drives to sit horizontally.

I decided to go with a hot swap drive bay for several reasons:

1. The SATA cabling adds to the general amount of cables in a system. A hot-swap enclosure has the cables attached to it, not the drives themselves. As drives are removed and installed the cabling remains unchanged. Cables can be installed (and hidden) away from view, and will not become messy over time.
2. Ease of replacing hard drives when needed, with limited space it actually could be impractical to have to screw a hard drive to a frame. The screws attach the drive to a rail (outside the case), and the hard drive (with rail) slides into the enclosure. This is the same way the apple bay works.
3. It felt like what Apple should have designed. The placement of the drive bays in the G5 seems a compromise, they are tucked away (especially the top one), and having to attach the cables manually seems mediocre. Clearly the biggest concern is the processor itself in these computers.

I choose a Lian Li EX-H34B. This has 4 SATA Hot Swap bay. This is designed to be installed into 3 x 5.25” drive bays. This looks like an internal component that can easily be stripped, and has many large holes for airflow. Many other enclosures look like sealed units so hard to know how well they could be adapted. The drive bay comes with all the mounting hardware, and includes 4 right angle Sata cables, which exit to the right, perfect for the G5 case.

I first disassembled this fully, removing the fan, and front covers, and 5.25” mounting and bottom of the drive, leaving just the bare frame. For reference the HDD drive bay when stripped down to the bear frame had the following measurements.

• Height is 128mm
• Width is 139mm including the flanges at the bottom.
• Depth is 186mm including space for cables at back, and and mounting rails protruding at the front.

The height of the bay is not an issue, and the bay has “just” enough depth to fit in with a few mm’s to spare when the front perplex cover goes on. The width of the bay is the only issue it is very tight inside the case. There are two additional changes I made to get the needed width.

1. The front IO port, I had to cut it down to gain necessary space. I am going to just solder to the underside pin connectors. I have seen other threads where this has been done (for fire wire) at least.
2. I needed to cut a groove in the fan mount, as the drive flange at the bottom poked out and come into contact with the fan assembly. (hence the standoff height to avoid the fan mounting holes)

I cut two strips of aluminum (from part of the cage I had removed) and attached them to the bottom (at the front and back) of the HDD cage, using existing mounting holes. This gives the frame back its rigidity and will serve as mounting points. I drilled 3 holes in these strips (and three corresponding holes on the top of the apple PSU cover) and attached the HDD cage to the Apple PSU cover using 22 mm spacers.

22mm was carefully chosen; it elevates the HDD cage (the flange that sticks out) above the CPU fan mounting holes, but not so high that it (the flange) interfered with the the front panel IO board. Finally it was just a matter of connecting all the SATA cables, and attaching the enclose to a power connector from the PSU.

Here are some pictures

 

[kiwisincebirth]

Front Panel Conversion

The front panel seems to be one of the unknowns for late 2005 builds, as there isn't an easy way to make an adapter. The connector itself is just pads on the board which match up to pins on the main motherboard.

In installing the HDD bay I had to cut down the board to allow the HDD bay to fit. My simple plan is to solder cables to the connectors on the board. The most important is the power (and led), at this time I haven't connected the USB/FW/Audio ports, but will follow similar process


The button PCB and main port PCB have three pins. The center of these is the shared ground pin. The outer two pins are for the switch and led (both positive positive) pins. A multimeter (in continuity/diode test mode) can be used to determine which is which. The power led actually glows when as a multimeter passes a small current.

I use a four pin header socket glued to the underside of the PCB, and soldered three wires between the two sockets. The wire I used is thin enamel coated wire used normally for wiring transformers, this wire is quite common at electronics hobby shops. The enamel provides an outer insulation but when heated with a soldering iron (and the enamel is burnt off and the solder adheres to the copper cable. This makes it ideal for soldering to small contact points


I used a low wattage (15w) soldering iron with a very fine tip (about 1mm) and fine solder (about 1mm), but preferably a temperate controlled iron with as fine a tip and solder as you can get.

The technique is as follows:

1. First solder three wires to the new four pin connector, the middle two pins are soldered to a single piece of wire. This is done (as mentioned above) by preheating the wire with solder to melt the enamel off (this is known as tinning), then wrap the wire around the pin, and finally heat and solder the wires to the pins
2. Glue the socket to the underside of the PCB, removing and surface mounded components that will get in the way of good contact between the PCB and the socket
3. Once set, the wires can be routed to the other side of the board and cut to length. You must ensuring that the wires are aligned to the pins on the existing socket. The only wire we need to connect precisely is the common wire that was soldered to two pins, it must be soldered to the middle of the three pins on the socket. The other two wires don't matter at this time.
4. To solder the wires to the socket first tin (apply solder and burn enamel off) the wires, and cut the wires so that the is just a small amount of tined wire exposed (1-2mm). Then hold the wire against the PCB with finger, to the the pin on the socket, and apply heat to the wire for a very short time, applying a small amount of pressure.
5. The motion is more like dabbing the soldering iron against the pins on the sockets. Because the pins (and wire) are very small they will heat up almost instantly, leaving the soldering iron for more than a second or so will cause the plastic in the socket to start meting, so just do a quick dab of the soldering iron, the join will either happen or it won't
6. To test a join use a multimeter. If it doesn't work repeat the procedure until it does then mvd onto the next pin. It becomes tricky at this stage to ensure you don't inadvertently desolder a join you have already made. This can be frustrating.
7. Lastly use a small craft knife to ensure that there is no inadvertent splatter of solder between the pins that will cause a short circuit. It is best to test this with a multimeter

An that's it. (well not entirely)

Lastly we need to make up the cable that attaches to the socket we just made, with the motherboard. I used two cables (power and LED) scavenged from an old case, then attached them to the plug that goes into the socket I just completed. It is at this point you need to determine which of the two outer pins is for Power Switch vs Power LED, but the centre two pins are common 0v GND pins and must be connected appropriately to the GND pins on the MB


And That's It.


Finally If you are interested in pinout of the PCB here are two topics I found on my travels.

http://www.insanelymac.com/forum/index.php?showtopic=88856
http://www.insanelymac.com/forum/index.php?showtopic=258071

 

[Mutts]

At present I have soldered four wires to the board, and have run these to connectors for the power switch and power led. I will post photos latter.

Agreed I wouldn't suggest anyone undertake this lightly, especially when 240v are concerned. However it really only involved modification of two wires for the fan, and two wires for the 240. The hardest part was removing the components from the existing power socket.

I considered this approach when I was doing my initial planning. Of your options I was leaning towards the mountain mods (or Lian Li alternative) simply because, it came with a complete back-plate to cover up the large holes left by the rear fans.

I spend a lot of time, just thinking about component placement before I came up with my design. That one of the things I like about these forums is everyone has these own skills and ideas, which leads to very unique designs. One of my skills is electronics but I had never used a dremel in my life.

Hehe I never used a Dremel before, but this project just screamed at me to buy one.
As for the MB backplate, I think ll go for the Mountain or Lian Li option. Especially for the off chance i screw up with the dremel
It is always handy to have an extra i/o backplate at hand.

Had a go with the PSU and i see why you and others opted for refitting.
It will take some room if u just put it on the bottom is use a http://www.bequiet.com/en/powersupply/250
Still i like it the way it is, so might put it in front at the botom and run the power cabel side ways.
It is becoming a nice puzzle to be honest to fit it all

As fot the front panel board, i'm looking to use an older version of it namely :Apple part nr. 922-5979, 630-4805 or 820-1560
One other thing i realised is that i trhew away the frontpanel connector wires of my old PC. So now i need to find those too

Good luck with the Mod.
I'll post some pics from mine when i get going.
So far stil planning and wondering if i gonna succeed

 

[kiwisincebirth]

Optical Tray

The optical tray require a small modification. I had to cut a small gap at the base for the MB tray to fit under. The HDD bays are unaffected, but If I install a full ATX motherboard latter, then I will have to cut the optical tray further, and remove the HDD drive bays.

I am running the existing power cable down the front of the case, to the bottom where it will connect to the PSU.

I first removed all of the cable ties from the cable, which made the cable much longer as there was now no bunching. I used a molex extension cable I had, removing the plug end and soldering the wires together to end the cable in a molex socket. I used a single grey paracord, getting all four power wires into the one cord.


I used a Molex to SATA converter to allow the Optical drive to be connected


I replaced the fan with a 80mm fan fractal design silent series, and replaced the existing sheathing with grey paracord, and heat shrink. I replaced the Apple rubber mounts with the supplied rubber mounts. I have not installed the downward pointing fan, that cooled the underside of the motherboard.


Optical Tray Assembly

I first mounted the top HDD bay to the top of the case. I then mounted the optical tray, And installed the case latching mechanism, and reconnected the external latch. Then mounted the lower drive bay, and HDD fan assembly


I labeled the SATA cable as A, B, and O (Optical), at both ends, to aid in identification latter.


I routed the HDD sata cables through existing hole and under the motherboard, with a right angle to come out near the Sata MB ports.

 

[kiwisincebirth]

Hehe I never used a Dremel before, but this project just screamed at me to buy one.
As for the MB backplate, I think ll go for the Mountain or Lian Li option. Especially for the off chance i screw up with the dremel

The best thing I found with learning to use new tools is to take your time. It is so.. easy to want to rush get the job done, ignore the urge.

Still i like it the way it is, so might put it in front at the botom and run the power cabel side ways. It is becoming a nice puzzle to be honest to fit it all

It is a big jigsaw puzzle which needs to be well planned, thankfully there are lots to people to get inspiration from.

One other thing i realised is that i trhew away the front panel connector wires of my old PC. So now i need to find those too

Never through anything away, especially bits of metal, they are raw materials for future work.

Good luck with the Mod.
I'll post some pics from mine when i get going.
So far stil planning and wondering if i gonna succeed

Thanks an let me know how you get on.