PSU for an old computer.

[ArisVer]

I am thinking of starting up an old Celeron300.
Is a 100W PSU adequate? It's going to have two disks, and three or four cards.

 

[Zap]

150W would probably be better, but good luck finding one that small capacity that is a normal ATX size. You can go for a Corsair CX430 just because it is cheap (often around $20 after rebate) and it has beefier 3.3v/5v for the older systems.

 

[dualsmp]

100w PSU *might* power it, but then again maybe not. If the PSU is shady quality, it might only supply 50-75% of its rating.

I think my dual celeron 533Mhz rig pulled a little over 100w AC from the wall at load, so maybe 65-70w DC since it was powered by an old PSU.

 

[ArisVer]

Are there splitter cables for PSU's? Is it a good idea to do anything like that?

The lowest PSU i can find online is 300W. It will be an overkill for that computer.
I will try and locate a 150W.

I can find a PSU at 300W or 350W from 25 euro, but i do not like is a huge fan rolling at night, that is another reason i want a low power unit.

I want to set it up as a file server 24/7, so it will be running two disks and one card constantly. I will also have a cdrom, a modem and a graphic card, used rarely. Maybe i will add a third disk in the future.

 

[ArisVer]

Some update. I got a 500W for my main rig. I had a lot of freezes, and it was the psu. 300w that i had was low. So, i'll be using the 300w for the celeron.

Instead of starting a new thread i'll post here some questions.

How can i measure the power i need for my computer? This must include mainboard, cards, cpu, ram, disks, usbs, ps2s. Is there a basic rule of thumb?

Also i expect the wattage displayed on psus not real. How can i know without using measuring equipment?