Does anyone know if the ps3 power supply can be swapped with an atx power supply and could a 60 gig ps3 use black power supply from the newer ps3's

As far as i know you should be able to swap the PSU from a 60 to a 40 GB PS 3

Newer PS3s draw less power than the original models, so you might overload a new power supply in an old PS3 model.

The newest (3rd gen, Black/Plastic)PSU's are larger and may not fit in an older case, without removing the memory card reader.
The original PSU, was overpowered in the first place(380W)I've never seen it run over 270W.
The second generation, post 2007, ran at 280W. So I would not see any issues with this.

I actually have a PS3 PSU running a 65W dual core computer /w 3.5 harddrive and laptop dvd

i have used a atx psu to power my ps3 but the 12 volts pulls alot of current, so you need around 20 to 30 amps.
hope this helps