When is a weak power supply TOO weak?

[Sexcow]

The power supply in my current computer is a 110 watt model and it's powering a CD-ROM, CD-RW, and two hard drives totaling 25 gig. I've got two 60mm case fans in addition to the cpu fan, also. I've been experiencing random lockups and crashes (which I expect with Windows), lockups at shutdown, and more than my fair share of coasters from my CD-RW drive, among other things.

I'm guessing that the amount of juice I'm drawing from my power supply is near it's maximum output based on the amount of peripherals and fans. Am I taxing my PS so much that it could be the cause of any of these problems? Is it possible to supply an inadequate amount of power to a peripheral, such as my burner, and cause it to still operate but perform poorly?

I'm going to step up to a better case and power supply in the near future but I'm curious as to whether or not the PS is the culprit...

[Roy]

I've read that the minimum spec for ATX supplies is 135W, if that tells you anything. http://sysopt.earthweb.com/forum/wink.gif

~Edit~
OOOPS! BIG TYPO! I MEANT 235W! SORRY! http://sysopt.earthweb.com/forum/frown.gif

[This message has been edited by Roy (edited 07-21-2000).]

[howste]

I've never used a power supply that was less than 230 watts. The smallest I've seen is 200. http://sysopt.earthweb.com/forum/icons/icon4.gif Are you sure that's not 110 volts? Anyway, if that really is how many watts it will supply, I'm amazed that you don't have more problems than you describe. Get it upgraded. You can get a 250 watt for under $20.

Steve

[This message has been edited by howste (edited 07-20-2000).]

[Sexcow]

Yup, it's definately 110 watts. It's a Delta Electronics Inc. power supply and the sticker right on the side says "OUTPUT 110W MAX". It is ATX too, which I forgot to mention. The funny thing is that I'm running a K6-2 400@450 in this computer with all those drives, yet I have 486s lying around with heftier power supplies!

Think my burning problems could be due to the fact that my power supply is SUCK or am I just kidding myself?

Sexc0w

[brandon184]

WOW. Thats the weakest power supply I've heard of powering an entire system.

Get it upgraded!

- Brandon

[tonym]

Sexcow (now that's a party name!!!),

The way you know if your PSU is underpowered is to add all the power drains for the stuff in your system for each voltage from the supply (Pd for +5V, Pd for +3.3V, Pd for +12V, etc.). If the total power draw is greater than 90% of the PSU rating (in your case 90% of 110W or 99W), then you're going to have problems due to transient power draws for disks and the mobo, and you will crash because the supply will go into current limiting. You can find the power draws for your disks and peripheral components either printed on them or in their manuals (it is required to be available!).
Now, you're probably asking yourself, how do I determine the power draw for my mobo. The tech support at your mobo mfgr. can give you this info (if it's not already tucked in the operating manual somewhere). They can give you approximate numbers for power draws of various CPU and memory config. combinations.
Unless you're O/Cing ;^)

A good rule of thumb for PSU application is to never get closer than 75% (0.75) of the PSU rating. I personally use 50% to allow for future expansion.

Now go buy yourself a new PSU! You can probably find a 300W ATX in the $40 range.


Tony

[paganman7]

You know your power supply is not strong enough when your LED's don't work! You should err on the side of caution and buy a 300 watt PS.

[Underclocked]

Just so you know, many HP Pavillions and other models hit the streets with a mere 90 watt power supply. My buddy just had to rob a decent supply from another case because of HP's powerhouse supply.

[Sexcow]

Underclocked hit the nail on the head - it is a Pavilion. I know they suck and I should have built my own, but I was quite a bit less knowledgeable about hardware at the time! It doesn't overclock worth a darn either...

I'm getting ready to put this turd out to pasture and step up to a T-Bird rig, but I need to find a good case. Anybody got any suggestions as to where to find high quality cases for a decent price? Most of the one's that I've seen are pretty dang homely...

[Wiz]

quite right underclocked. I had a HP once, 110watss of pure power. I had a HDD< 2 CD-Roms, zip and an cdrw before i noticed a loss of power though.

[Underclocked]

The Fong Kai cases are nice looking (they make the HP cases). Check at http://www.directron.com/fk320.html for the Athlon approved FK-320 .

[Sexcow]

Thanks for the help everybody, and thanks Underclocked for the heads-up on the Fong Kai cases. I'm still trying to decide between the FK-320 and the FK-603 'cause they're both so **** sweet!

Sexc0w

[JC]

Get the FKI 320 Super mid tower because it is cheaper and it has the 300watt AMD approved psu(if you add the smaller one plus the 300w AMD psu it turns out to be cheaper). Also, it is bigger and you can get it in black.