My Blizzard PPC works flawleslly, and the +5V line reads 4.89V. This critical difference that some people find, is actually related to the components quality. Even in the same production batch, eletrical parts may have differences.
These capacitors that i mentioned, usually change their internal resistance (i don't know the exact word in English for this. In Portuguese we use a word that means 'escape')and so the circuit have problems working properly, because this way the voltage goes down. Ans doesn't matter what kind of power supply you use to feed the circuit, the voltage will not raise enough. In fact, if you try to raise the current, these faulty capacitors will soon fail.
Sorry, it's a little difficult to explain this better in English. But i really think that you should replace these parts.
Regards,
Marcelo.