Here's OnDaEdg's article.
Ok, here's the problem: when OnDa hooked up the 2 PSUs together, he got "almost 13V" on the 12 V rail. That might be good for a Pelt, but it's no good for a PC.
The link in the article suggests using a power diode to prevent currents from flowing back into the PSUs, which is good, but it drops the output by 0.7 volts (as all diodes/junctions do), bringing down the 12 V line to 11.3. Still no good.
On the other hand, if I experiment with this, and I do get 13 volts, I can bring it down to 12.3 with the power diodes.
For reference: 12V +/- 5% tolerance gives a range of 11.4 to 12.6.
Anyone?