So, after nearly forgetting that I ordered one, I received my shiny 512MB Pi the other day and had nothing but trouble with it. It simply stops working after a few minutes. I can count myself lucky if the system manages to boot at all.
Since I'm a complete newbie, I ordered a complete package from RS Components - a Pi, a click-together-case and a power supply specifically intended for the Pi. From my own parts bin, I got a slimline Hama USB keyboard, a no-name USB mouse and a brand new SD card with Raspian 'wheezy' on it. To see what my new Pi would be doing, I hooked it up to my HDTV via a basic HDMI cable from amazon.
I plugged in keyboard and mouse, fed the SD card to the Pi, hooked the system up to my TV and finally connected the power supply. Io and behold, a wall of text cascaded down my screen. Seems like everything worked flawlessly! But then, while I tried to make sense of the raspi-config menu, my screen went dark and my TV told me that there was no signal on that channel. I switched to normal TV and back to the HDMI input, but still nothing. I checked the Pi itself - a red LED was on, but nothing happened. I tried the keyboard, the mouse, nothing.
Trying to eliminate possible faults, I tried the HDMI cable with my PS3, which worked without a hitch. So it wasn't that.
I thought "okay, maybe the power supply is inadequate after all" and got myself a powered USB hub to take the power drain from mouse and keyboard off the pi, but still the same results. I can hardly boot up the thing before it goes dark again. WHAT THE HECK, guys? Help, please?