As per title. Please, I'd like to hear about both Psionics Unleashed and D&D 3.5.
Can a psion 3th with Intelligence 11 augment a power to CL 3°? Example:
Magath is a Shaper 3. His Intelligence is 11. Can he manifest an astral construct with 3 pp with everything it brings?
I think the answer is yes. Witness a 2nd level psion. They can augment a power to 2pp, which is more powerful than a 1st-level power starts out at. Also, saving throws don't increase unless specifically stated, so there's precedent for the power-level not actually increasing.
The other thing I'd dig for if this was important to me would be concentration checks. Does the DC for a concentration check go up just because you've augmented the power? That might illuminate what's intended.
Yup, the most important rule in all of psionics is that you can manifest power points up to (never more than) you manifester level. Any effect that allows you to manifest more PP at one time does so by increasing your manifester level first, so this rule is never ever broken.
That said, said psion cannot augment anything other than a 1st level power, because he remains unable to manifest anything more powerful.
Yeah, it's important that you don't neglect the cost of the original power. You need to factor that in.