1202 ALARM

I was given a broken Acer monitor recently which was powering up but not displaying anything. I took it apart and was surprised to find this, but not where I expected it. The capacitors in the main power supply were fine and the supply was giving out the correct voltages, but for some reason Acer (or whoever made the power board) had decided to use a different manufacturer's capacitors for the part of the circuit powering the backlight inverter and 3 of these had blown. You can clearly see the top of the capacitor has been pushed up and evidence of leaking electrolyte in the 'hot-cross bun'. This looked like an ideal candidate to test my new capacitance meter I got on Amazon and received (from China of course) only last week. The capacitor is marked as 1000uF, so let's see what it is actually doing now. Oh dear, only 230uF and probably on it's way to a dead short. Unfortunately one of the other ones looked like it had exploded and had shorted

Just watched 'The Imitation Game' on Film4, the excellent drama about Alan Turing. By coincidence I dismantled this oddity today. It's a Butterfly Labs Bitcoin miner, now obsolete, but capable of processing 60 million SHA hashes per second (you read that right). Apparently today you need about 800 million per second as Bitcoin mining becomes increasingly difficult. The Bletchley Park 'Bombe' computers did basically the same job as this thing only many orders of magnitude slower. This thing isn't a computer, but a dual ASIC, Application Specific Integrated Circuit. It had 4 fans (count 'em) to keep it cool and drew about 1Kw of power. At best you could mine a couple of hundred Bitcoins a week back in 2013 when this became available. Butterfly Labs have since been forcibly closed down by the US courts.