Total computer nerd question for Lopaw.

Sorry for the off topic post, but knowing that lopaw likes to build computers I have an upgrade question she may be able to help me with. Any of you that think this will be hot talk with a lesbian, well unless power loads turn you on, you'll be disappointed.

Lopaw, forgive the imposition, but perhaps you can help me. I'm upgrading my old G4 Mac and I am running into some power issues (I think). I've replaced the old drives with a Seagate 120GB and a WD 80GB in the built in ATA bay. No problems, runs great. I replaced the old optical drive with a new Dual layer. Again, runs fine. I have two PCI cards, one a Firewire (2 ports) the other a USB-2 (4 ports). I will probably upgrade the processor to a 1.3GHz, but I don't think that presents a power issue since it runs off the motherboard (correct?). Now, my last planned upgrades are for a new video card and a PCI ATA controller to run two additional 320GB WD drives in auxilary bays in the computer. The video card will be an older model, like an ATI Radeon 8500, so I shouldn't tap more than the AGP bus for that, which is about 40W. Are those last two drives going to make my power supply (200W) go poof? I looked up the specs on the drives and most are around 10W for continual seek, and the optical is 12W. However from what I've heard, the startup on drives can be nearly 30W! Being an EE, do you know where I can get some specs on these things? I wasn't able to confirm that looking at the manufacturers info on the web. When I add things up I get about 180 Watts as the load with everything running, but if the drives are going to draw 120W at startup rather than the 40ish I figure on, I'm looking at a new power supply aren't I?