Anyone use anything like the following: http://www.amazon.co.uk/LEDER®-Flexible-GARDENS-AQUARIUMS-KITCHENS/dp/B003N8ESHW/ref=pd_sim_light_3 Says it will run off a standard 12V supply. Rather than buying the 3 I would need, do you think it would be possible to run off an old Pico PSU I have if I just cut the wires off the Molex connectors and soldered them together? Obviously I would disconnect the remaining wires from the PSU. If possible I would also get some new wire and extend the cables through the plasterboard so I can run all 3 sets off the one PSU.
Just looked up the specs. The maximum current pull of a single 3528 SMD LED is 30mA, which means 360 of those will pull: 360*0.030A = 10.8 Amps, which times 12v will be just around 130 watts. Adjusting for differing load levels and the inefficiency of any circuit I would say a 150w PICO PSU should be up to the task.
One thing to keep in mind is that those LED strips are RARELY ever hooked up with a single LED + resistor from 12V -> GND. It would be safe to assume that the LEDs are hooked up in the typical 12V strip configuration of 3 in series with a single current limiting resistor for the sub-array. This reduces parts count and also reduces power dissipation in the current limiting resistor, since it now only needs to deal with 1-2 volts instead of 8-9 volts. All it would take is a quick visual inspection to confirm, but if that is the case then really your math is more like this: 120 LEDs per reel * 3 = 360 LEDs, but hooked up in series of 3 + current limiting resistor with each sub section drawing 30 mA; and you are really looking at 120 sections of 3 LEDs. Each section of 3 + resistor would draw 30 mA. so 120 * .03 A = 3.6 A at 12V. This equates to 43 watts of power [not including voltage drop over the strings themselves]. To be safe I would go with 4-5A but to answer your first question: I agree with Picarro, you can easily use a computer PSU for this. Just remember which wires you need to jumper to turn it on.
