Tony Duell wrote: Another factor after reading many posts here, is power supplies often have power on -- power off sequences for core and other computer logic : Power fail IRQ for example. A modern PC power supply may not have that.

Cameron Kaiser wrote: In the case cited, there seemed to be no reason not to fix the PSU - especially as it is not likely to be significantly easier to design a replacement than it is to simply fix the original. Slapping in an AT or ATX PSU (or PSUs) with no further modifications is not likely to work (especially if the intent is to use more than one such PSU). The C=64 brick is notorious for its lack of relaibility. If mine fails, I'll no doubt look to replacing it with something more sensible. A reversible modification to replace the PSU (which in the case of the C=64 is obviously going to be trivially reversible) would not cause me too much heartache. Similarly, replacing the linear PSUs in some old iron with modern switchers of much greater efficiency is something I would contemplate if that meant that I could afford to _run_ said old iron. Again, that would need to be a reversible modification and te original parts retained for future replacement. Until I get some old iron that fits the bill, this part will remain purely hypothetical :-) Antonio -- --------------- Antonio Carlini arcarlini at iee.org

Tony Duell wrote: You could get a third-party replacement C64 PSU which was a switcher. No, I don't know how they did the 12V AC line. They were incredibly reliable, ran very cool, and a fraction of the weight of the originals. Gordon.