Firstly on the top, you will want to remove the components in the spaces marked red. You can also remove the RJ45 connector if you wish.
On the flip side, you can also remove the SMD components marked in red. The crystal might be a little difficult to remove, but as before if you don't want to re-purpose it, you can just load it up with solder and keep the heat on it until it slides away. Otherwise you can use the same technique used with the gas torch:
Now you can remove the USB connector and change it with a single port variant.
You will now have an almost indistinguishable Model A Raspberry Pi.
Why all the fuss you might ask? Well lets have a look at some figures for the 512MB "Model A" Raspberry Pi.
Power usage comparison with the other Raspberry Pi models (the Model A here is the original pre-production model).
From the page:
352mA - Model-B Running stress test
330mA - Model-B Idle
143mA - Model-A Running stress test
118mA - Model-A Idle (with HDMI connected)
110mA - Model-A Idle
107mA - Model-B After "sudo halt"
33 mA - Model-A After "sudo halt"
From my tests with the 512MB Model A with a lab supply at 5.00V:
35.29mA - After "sudo halt"
106.9mA - Idle (avg)
111.1mA - Idle (avg) (with HDMI connected)
163.5mA - Running stress test
165.9mA - Running stress test (with HDMI connected)
265.2mA - Stress Quake 3 (avg) (with HDMI connected)
My CPU stress test was run with:
cat /dev/urandom |gzip > /dev/null & md5sum < /dev/urandom &
It looks like it draws a little extra current while stressing over the 256MB Model A. This would undoubtedly be due to the doubling of the RAM.
Juggling with RAM sizes by giving 256 to the GPU and 256 to the CPU (in /boot/config.txt) yields the following:
160.6mA - Running stress test
163.5mA - Running stress test (with HDMI connected)
While this doesn't disable the RAM, it shows that the larger module size is a direct factor to the extra current draw over the stock Model A (the bits don't require charge to swap about but they still need to be refreshed in this instance). Still, 512MB with a slightly higher draw is definitely favourable.