Power requirements for all devices shown

[eurodaiz]

After having a HDD slowly die on me by intermittently powering down then up again, i started trying to find out how much power my system really was using. I stumbled across this at PC power and cooling:
http://www.pcpowercooling.com/maxpc/index_cases.htm

Now, that's all well and good but when i started adding these figures up, the numbers were crazy. eg my Enermax 350W PSU says that the 3.3 and 5V combined sould not be more than 185watts but my stuff adds up to like 224W.
Now, here's my question some of the components as you can see use both 3.3 and 5 or 5 and 12 but is this at the same time and should they be added into the same number??

Below is my system. are there any electronics/electrical/computer buffs that can tell the rest of us how much power a high end system would use.

Athlon XP 1700+ @ 1900+
> 512 mb DDR Kingmax/Crucial
> Abit KR7A-RAID
> Geforce 2 GTS
> SBLive
> NIC
> Maxtor D740X 20Gb - Primary Master on Promise IDE1
> Maxtor D740X 20Gb - Secondary Master on Promis IDE2
> Seagate Barracuda IV 40Gb - Secondary Slave on Promise IDE2
>
> Plextor 16X CDR - Primary Master VIA IDE1
> Toshiba 12x DVD - Secondary Master VIA IDE2


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damn.........my chain's too short

[AMD Guy]

I would say you should be safe with a 350-400W quality ATX power supply. I have a similar setup running on a 300W enermax power supply.