Not enough juice? Solved...

[Xayd]

Was having trouble with my new machine today, got a new drive in it and decided to copy over everything pertinent from my primary machine's backup partition (downloaded apps, mail settings, bookmarks, etc.). This machine has my Kenwood 62x, two hard drives, floppy, ISA modem, Voodoo card, yadda yadda.

Problem, case has a buncha fans attached to it (four to be exact), and I didn't have enough power connectors left for the new drive! Well be damned, how am I gonna get all these drives working without enough power connectors? I'm also getting weird voltage fluctuation reports from the Asus monitoring utility, so I might be reaching the limits of this 250 watt PS.

Then it dawns on me, why not use an old AT power supply in conjunction with the ATX power supply in the machine now? So I fixed a switch on an old AT 235 watt PS and hooked all my drives to it, fired everything up and voltage fluctuations are gone, all drives working great.

Plus, it's just cool having to turn on a buncha switches to fire up my machine, like a pilot having to flip a buncha stuff to fire up a jet airplane, just makes it sound powerful .

Xayd

[Tiretool]

I've always stood behind using a 300W PS as a bare minimum for this exact reason. Never have to worry about running out of juice.

I bet that monster is loud!

Got Earplugs?

[hackercarlos]

[Xayd]

Four case fans are loud anyways. This is just fuel on the fire. I think I may have to break down and go get a 350 or 400 watt PS eventually. Meantime, though, it works with three hard drives, heh.

Xayd

[Toaster]

Hmmmm...lets do some math.
You have a 250Watt supply. It prolly can produce 8 amps of 12volt current, 15 amps of 3.3 volt current, 12 amps of 5volt current plus minimal -5volt and -12volt. (these are approximate)
A CD-ROM drive uses about 1.5 Amps of 12volt and about 1.0 amps of 5volt curent. 3 case fans and one P/S fan consume about 1.0 amps or less. 3 hard-disks draw about 1/2 amp of 12 and 5 volt power. Thats about 1.5-2.0 amps total on the drives. The floppy uses about .75 amps during a seek and the system board eats about 8amps of 3.3 volt current and about 5 amps of 5 volt current. The system board uses very little -5/-12 volt current. Ok, with these numbers, whoop out your caculator and compute total power used in *watts*. The total comes to about 96 watts or about 40% of the capacity of the supply. If your voltage readings are unsteady, the P/S may be "under-loaded" or just a low end power supply. The remaining option is that the monitoring S/W is inaccurate.
(the above assume IDE devices)

[PoolTrout]

well im not doing that math but thanks for the tip..

[Xayd]

I have no doubt that it's a flaky PS, it came with a 40 dollar no name case .

The problem wasn't that the PS didn't have enough juice, though, just didn't have enough power connectors, too many fans, no Y connectors.

Xayd

[glc]

You can buy "Y" connectors for $3. My box is full of them.

[PC_Rookie]

Wow, now this is a site I could really benifit from....

[Toaster]

A little something to keep you folks on your toes concearning "Y" type splitters. The cheaper type utilize very small wire and add "inductance" and "capacitance" loads to the power supply. This can cause instabilities. Locate and use the heaviest guage thats available or the shortest. Perferably both. Wire guage should be no less than 18ga. and its total length should not exceed 6 inches.