Power Supply and Cold Cathode Question

I am working on a project and I will be using 30 cathodes (not a typo, got them dirt cheap). I would like to power them with one PSU but i dont know how big of a power supply I would need or if I would need two. The cathodes will be hooked up to dual inverters so there will be 15 total inverters. Any ideas on how big of a PSU(s) I would need to power the cathodes? I dont know much about how much power n stuff the cathodes would use.

FYI: Im not going to say anything about the project since I think it will be fully original and dont want to risk someone doing it before me . BTW: It will be a big (literally big) pc mod. All I will say is that it wont be a case made of cathodes or anything wierd like that.

I did a bit of google mining and each cold cathode draws about 2.5 to 3.5 watts so 30 of them will draw up to 105 Watts. Allowing for loss across connectors and the inverter you should put aside about 150watts. One other thing to bear in mind is that many power drains turning on at once may creat quite a surge. It might be worth getting hold of some timed relay circuitry to bring them on in timed groups once the power comes on, might look quite pretty

Oh as ever, PICTURES please

The cathodes would have a dedicated PSU due to the draw i thought would happen. I also thought about just having diff sections of cathodes on different switches, but i like the relay part.

If I used a relay how long should I wait in between groups? A few seconds or less? Also, coin thanks for the info on wattage.

a second or so should suffice. if the cathodes are powered on with the psu, you might not have as many problems as when you power them up seperately. i have seen instances where powering up a cathode when the computer was running would nuke a psu. dont rember what brand it was though. some dirt cheap 550. if you have some old at power supples, test on those. they are almost useless and easy to power up.

edit:
can't wait to see what you have in mind. with that many cathodes your could shine deer with your computer!
/edit

I would buy a smaller regulated PSU to run the cathodes, rather than a second ATX PSU. You'll get cleaner power and they will run silently. Some of them also have 5v outputs in addition to your 12v rails.

Example:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2568612067&category=32720