replacement power supply

I have been using a cheap Chinese power supply for my reprap for the past year and a half. It died tonight. When I did a post mortem on it, I found what I think is a ceramic capacitor that was burnt to a crisp to the point where it crumbled between my fingers. I'm not so sure I want to replace it with another one, so I started looking at PC power supplies, but I wanted one that had modular cables so I could remove the unused ones. While browsing newegg.com, I came across this power supply. Its not as full featured as the normal pc power supplies, but it has two 12v 20a rails and it is only $25. It also has modular cabling.

Unless someone points out something I am missing, I think this is the route I am going to rake.

BTW. There is another ongoing thread about PSUs.

I also seriously considering swapping to a ATX power supply, after a cheap Chinese one that I just bought, blew up.

One thing to note however about PC PSUs is that they have a minimum load on 12v, and will not output anything at all if this load is not present.

To get around this I'm thinking of putting in a LED light on my printer.

If you are going to spend money (as opposed to use a scrap part) get a good industrial supply. Mean Well makes good parts. TDK / Lambda also makes good stuff. Get one from a dealer rather than on eBay. You should be able to find a 12V 30A supply for about $45 (US). They are smaller / lighter / better regulated than a normal PC supply. They are rated for constant use (with rating sheets and reliability data). They can be adjusted over a reasonable range. You might decide that +14 is better than +12 at some point ....

I just realized that this power supply does not have an on/off switch. Instead, it connects via a Molex connector to the main power supply to know when to com on. If it's just looking for a switch closure on this connector, then that could be accommodated, but I'm assuming that it's looking for voltage - either 5 or 12 - to turn it on. This is not a workable scenario unless I open the case and find that there is just a relay I could bypass.

Bottom line is that this is not the solution I thought it was. I think I'm going to look into a domestic manufacturer - like Meanwell - of an industrial supply. I took a quick glance at a site (not ebay) offering meanwell supplies. They look like they're housed like the power supply that needs to be replaced, which has the advantage that I could just reuse my existing wiring harness.

If you really want to spend some time on it, MeanWell posts information on MTBF and temps on all the parts used in most of their supplies. It’s a wonderful read if you are about to take a nap anyway

Putting a MeanWell next to a TDK/Lambda – they obviously look at each other’s design. They are not identical, but they are mighty close. Both seem to be using pretty good caps with reasonable ratings. That’s often where the problem is on these beasts, failure wise.

There are an almost infinite variety of power levels, voltage ranges, and features on these. I’d take a close look at +12 (+/- 1.5 to 2V) vs +15 (+/-1.8 to 2.2V) as a nominal output. I’d also consider if 30A is enough / too much / not enough for the immediate future. I don't think I would pay more for power factor correction or sense leads.