ATX bench PSU

[Arcade-Projects]

Time for an upgrade! My previous ATX bench supply was without me knowing it causing all sorts of video issues. After identifying the problem, it was time to get a new one, and I've picked up a Cooler Master MasterWatt 650W. ATX power for arcade is just fine, but using an old beat-up recycled thing may not be ideal unless you have a way to verify that is's working ok. A multi-meter will not do the trick unfortunately.

You're never going to need 650W, but the nice thing is that even with ~5A on the 5V rail, which is about as much as you will ever see - it stays quiet with no fan activity. Also nice with this one is that it doesn't have a ton of cables/connectors attached, and that the 24pin cable is a little longer than normal. The ad for it says 16AWG, which turned out to be bogus - the 24pin is plain 18AWG.

arcade-projects.com/forums/ind…c1693b190c4c379900e6e6433

Scope time

This was the root cause of issues I had with the old one, ripple about 0.17V when loaded ~ 4A:
arcade-projects.com/forums/ind…c1693b190c4c379900e6e6433

This is the cooler master, with a ripple of about 30mv, or 0.03V which is really good:
arcade-projects.com/forums/ind…c1693b190c4c379900e6e6433

For reference, same setup with my linear Rigol DP831 fancy lab supply:
arcade-projects.com/forums/ind…c1693b190c4c379900e6e6433

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