by René Pawlitzek, rpawlitzek@hotmail.com

What do you do with a 10 year old PC? An AMD Duron with 1GHz, 1 GB RAM (PC-133), and a 20 GB harddisk. You have two possibilities: a) You throw it away and buy a brand-new PC or b) you rebuild your old PC with a new motherboard, new memory and a new harddisk. Luckily, the PC industry has come up with standardized components that allow you to exchange parts easily, at least most of the time. I chose to go with b) because I was not yet ready to throw away my reliable PS/2 Cherry keyboard, my ergonomic PS/2 Logitech mouse, my brilliant Philips 19“ LCD energy star monitor with VGA connector (16.5W power consumption), my lovely MaxData PC case with its quiet Delta power supply, the LG CD burner with IDE interface, the Epson printer and the parallel printer cable, and the aging Windows XP Home operating system that I have used and appreciated for so long. My plan was to reuse all these components in order to avoid waste and at the same time build a new system with low power consumption. In other words, I decided to build the ultimate Green PC, powerful enough to do daily work and energy efficient using some parts from my old PC.

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Philips 190SW monitor		MaxData PC case

The challenge was to find a new power saving motherboard that could connect to all the legacy components. I did find such a board on the market: the Gigabyte GA-D525TUD. This motherboard comes with an Intel Atom D525 dual-core processor. A CPU that is fast enough to surf the web, to create Microsoft Office documents, to watch YouTube movies, to listen to music, to look at photos, to read and write e-mails, and to chat over the internet. The processor has a max. TPD of 13W, 2 cores and hyperthreading. Unlike many other motherboards, the GA-D525TUD features a number of legacy interfaces to use older hardware. It has an IDE interface to connect PATA disks and CD/DVD burners, PS/2 connectors for mouse and keyboard, a VGA output to connect an LCD monitor without DVI or HDMI interface, a parallel printer port to connect older printers without USB port, a PCI slot and surprise, surprise a serial port to connect ancient 56k modems. An excellent fit for my project! In addition to all these legacy interfaces (PS/2, VGA, IDE, PCI, parallel and serial port), the GA-D525TUD includes 8 USB 2.0 ports, a Gigabit LAN port, and 4 SATA ports. The board also supports RAID 0, 1 and is therefore suitable for building a NAS (Network Attached Storage) device. Gigabyte is known for its reliable motherboards and the GA-D525TUD is without any doubts a high quality product. It contains a DualBIOS and apparently implements Gigabyte's Ultra Durable 3 technology for a long lifetime. The board includes the Intel Atom D525 processor and sells for CHF 104.00 here in Switzerland. In addition to the board, I bought 2 x 2GB DDR3-800 ValueRAM from Kingston for CHF 45.00 and a Western Digital WD5000AADS 500GB 'green line' disk. The disk is very quiet (21dBA idle, 22dBA seek), very power efficient (4.13W read/write, 2.18W idle, 0.77W standby, 0.75W sleep), and costs CHF 45.00. A good match for the Gigabyte motherboard. Gigabyte GA-D525TUD motherboard

My biggest fear was that the new GA-D525TUD motherboard would not fit into the MaxData PC case. Before placing the order for the board, I checked on the internet if the board's Mini-ITX format (17 x 17 cm) was compatible with the ATX standard. Luckily, ATX and Mini-ITX are compatible. All the holes for mounting the board are in the right places and putting the board into the old MaxData case was an easy task. Next, I connected the IDE cable to the CD burner, the two power connectors, and the USB cable to the front of the case. The front panel connector for power, reset, power LED, and harddisk LED had to be rewired because it was connected to the MSI-6340 motherboard using a layout which is not Intel compatible. This required some work and was the biggest obstacle when assembling the hardware. Connecting the harddisk required a power adapter, because SATA disks no longer draw power using a 4-pin Molex connector. Such an adapter is CHF 9.30 here in Switzerland. I was surprised how easily I was able to replace the old motherboard and harddisk with the new components thanks to the PC industry's standardization efforts. Gigabyte GA-D525TUD and Western Digital WD5000AADS in a MaxData PC case with space for rent

I decided to reuse my old Windows XP Home operating system well knowing that this software is about to be phased out in the near future. However, I still like Windows XP despite being a Windows 7 user for a quite some time now. But why should I throw out something that still works perfectly? The installation of Windows XP Home and the GA-D525TUD device drivers was painless. The system recognizes 2.99 GB of RAM, and the 4 execution units of the Intel Atom D525 CPU (see below). I had no issues with the software that I have used on the old PC. Everything still runs, only faster. This is what PC compatibility is all about! Dual-core and hyperthreading

I am more than happy with my new Green PC. It could be called the ultimate Green PC, because it was build with reused components from my old PC and it also contains a new state-of-the-art motherboard / CPU combo which is quiet and energy efficient. Now let's have a closer look at different aspects of the system:

• HD: Harddisk space went up by a factor of 25, from 20GB to 500GB. A huge improvement.
• RAM: The new system is able to use 3GB of RAM. The old system had 1 GB of RAM. Improvement by a factor of 3.
• Speed: The new setup has now a dual-core CPU with 1.8GHz, hyperthreading, 800 Mhz RAM (DDR3), and a much faster disk. Needless to say, that you can feel the difference. According to Passmark.com the Intel Atom CPU is roughly 3 times faster than the old AMD Duron 1GHz processor.
• Noise: The Atom CPU doesn't generate a lot of heat thanks to its max. TPD of 13W and the motherboard's fan can work very quietly. Also a big improvement.
• Power consumption: The new system requires 38.3W when idle and roughly 43.5 W when running with load. I had hoped that the power consumption would be even a bit lower, but I assume that the old, reused power supply has only an efficiency of 70% preventing a lower value. The old PC used 65W when idling and typically 80-120W when doing work. Improvement by a factor of 2. The power consumption of my complete PC system is now: 65W = 40W (PC) + 16.5W (LCD) + 5W (ADSL Modem) + 3.5W (USB Hub)
• Cost: The new components cost CHF 203.30 in total. A comparable, brand-new system is around CHF 500. Cost saving by factor of 2.5.
• Fun: Endless! It was so much fun to evaluate, order, build, setup and measure the system. It is even more fun to use a unique system that you build yourself. And finally, it makes you feel good to know that you have reduced waste by reusing components and that you save energy whenever you use your PC.

The Green PC uses roughly 40 watts.