Model 4/4D/4P Power Supply
Jay Newirth is now selling Model 4/4D/4P power supplies using modern day components! One version is an all-in-one board where you simply remove then old one and swap all the cables from the old one to the new one. The other version has a much smaller board which screws to the holding plate, but has the power supply units separated for mounting at the bottom of the case.
You can find them at the NewSoft Store.
v2.0 – Supplies mounted to bottom. This would be for older Model 4’s.
v1.0 – All-in-one unit.
The Model 4/4D/4P uses 4164 chips. These are still generally available although you need to be careful of the source. Fake chips (or chips that will fail) are very much a risk, so it is important to source them from someone who has run them through a RAM tester. There are people who sell based on how much they have on hand, and you can always try your luck on eBay.