Lazarus Project - Components and Thermals

Component Inventory 

I have secured a donor unit, and installed some PC hardware. everything fits!

Let's start by reviewing the inventory:

PlayStation 3

The unit that I will be reanimating is a CECH-A01 model. This first-generation model is one of two models that included the processor from the PlayStation 2 for full backwards compatibility. It was available with a 60 GB hard drive and included 802.11a/b/g WiFi. There are three reasons why I am interested in using this model for this project.

1. This is the same model of PS3 that I had when I was an impressionable youth. Nostalgia is a potent drug for us millennials.
2. This model included 4 front-facing USB 2.0 ports. Other, later models of PS3 included only 2 front-facing USB 2.0 ports.
3. This model and the CECH-C01 (60 GB PAL) and CECH-D01 (80 GB NTSC) models were the only ones to feature a memory card reader. The memory card reader is concealed behind a flap beside the optical disk drive slot.

I bought a broke PS3 on Kleinanzeigen, the classifieds website. Irritatingly, the seller neglected to include the case screws, so I will need to order those separately.

PC Motherboard

I have acquired a mini-ITX motherboard with a decade-old quad-core Intel CPU with an 80W TDP, and 32 GB RAM. There is a 500 GB SSD. This hardware is fairly old, but perfectly adequate for home-server applications and is also perfectly serviceable for the thermal benchmarking that I'm interested in performing.

Power Supply

For power, I have chosen a 250W DC/DC power supply built by HDPlex. This is an older model, but it follows the same footprint as their newer 500W GAN DC/DC power supplies.

Mounting Caddy

I designed a mounting caddy to hold the motherboard and power supply in the PS3 case. Many of the other builds I've seen online chose to mount the motherboard directly to the plastic case, but I didn't want to do this for a couple of reasons:

1. The case is not designed to have heavy motherboards and heat-syncs mounted to it, and I would need to drill mounting holes in order to securely affix the motherboard standoffs to the case, and these would be visible on the outside.
2. I wanted to be able to experiment with different cooling orientations

I have used two different mounting caddy strategies: the first was to hack up an existing ATX PC case, and the second was to design a caddy out of laser-cut acrylic. The ATX case was nice in that I was guaranteed to have the standoffs correctly spaced, but it is difficult to replicate, since each case is a little different. 

I roughed out a caddy in inkscape so I could try it on the laser cutter. This turned out quite well, I was able to mount the power supply and motherboard securely! The laser-cut caddy worked quite well. I used standoffs to offset the caddy so it could be affixed to the mounting posts in the PS3 case. 

The caddy holds the motherboard and power supply, and has brackets that mount on mounting posts that hold the PS3 case together.

 

Here the caddy is installed. Observe the two cooling fans at the top, that pull cool air in and blow it across the power supply and motherboard. This creates a positive-pressure environment, and warm air exhausts out the sides.

Thermal Testing

I tested the thermal performance by sealing up the case and running a CPU workload. I chose Prime95 and let it run for about 30 minutes before taking any measurements, then ran it for about 2 minutes in each configuration. I used htop to monitor the CPU temperatures and clock frequencies. I wanted to see how much the CPU reduced its performance in response to high temperatures. For a control, I took a measurement with the case open, as in the caddy figures above. As you can see in the graph, the CPU throttled a little bit when the case was oriented horizontally, but not when oriented vertically. 

 

 

 

Case sealed up in vertical orientation

Thanks for reading this installment, see you next time when we talk about the interface control board!