Anyoneout there have a clue about calculation power consumption?

Before I buy a new PSU I had a look at my old one.

It's a Enermax 350W and the label states these specs:

Enermax EG365P-VE

+3.3V +5V +12V -5V -12V +5VSb +3.3&5V Total
32A 32A 26A 1A 1A 2,2A 185W 350W

105W 160W 312W 5W 12W 11W 185W 350W

The last line is my calculated Watts for the lines,
strange that the sum of the individual lines is much
higher than the total (it's not on new PSUs). Is this
something fishy, or what does that really tell you?

As you see it has only one 12V line, and this today powers:

- Asus P4PE mainboard (with Promise S-ATA raid ctrlr)
- Intel P4 2.54 Ghz (478 socket) with stock fan
- Creative SB Live 1024 PCI sound card
- Plextor PX-716A DVD-writer
- Samsung Spinpoint 120 250GB S-ATA harddisk
- Asus V8440 Nvidia Ti-4200 video card

Now, if I replace the video card with a 7600GS
will this work, or will my PSU give up on me.

How much Amps will the other stuff in my rig use?
It's the CPU that takes most juice here, right?

Is there any tables or any experiences that would
help me calculate this? Or do I need a new PSU?
--
Lars-Erik - http://www.osterud.name - ICQ 7297605
XP, Asus P4PE, 2.53 GHz, Asus V8420 (Ti4200), SB-Live