Voltage Question

[CommanderC]

Ok, I dont know why, but i have a feeling that im stressing the current 115V im running at, heres what Im running: 2 HD's, 2 CD-rom's, Floppy, Fan, MB, Celeron 500, Riva TNT2 Ultra, SB PCI 128, Intel Networking Card, USR Modem. Would turning the voltage up hurt anything (I have a fear of this after tinkering with the voltage on my Portble CD Player.. lets just say it was fun taking it apart...)?

[LazMan]

I suppose nobody has replied to this because they figure it's beyond their ability or knowledge OR they figure anyone asking such a question deserves the consequences of playing with fate...

First, you do have a LOT of devices that are asking for power resources. Every card that plugs into the motherboard sucks a bit of juice. The more the card is used and the more chips on the card the more power it wants - it's a vampire! There is a reason we have video cards known as MONSTER! This sucking of power is known as CURRENT FLOW from the power supply to the devices in your machine.

If you've taken any electronics or studied it in some science or physics class, you've heard of the age-old PIE equation (P=IE where P refers to POWER, I refers to CURRENT, and E refers to voltage). Since a large majority of power supplies these days are rated at 235 Watts, and the input voltage from your wall is known to be somewhere between 110 to 120 volts, the maximum current draw (that is, the sucking capabilities of your machine as a whole) is I=P/E or 235/115 (I always use 115 as a generic medium) which is a maximum of just a hair over 2 amps. Look at the equation for just a second more, then answer this question: if you increase voltage, what happens to the current (assume power will always be constant)?

An analogy of electricity is water running through a water hose. POWER is the amount of water traveling down the hose , VOLTAGE is the size of the hose, CURRENT is the rate of flow of the water. Increase Voltage, increases the size of the hose giving more room for water to flow and reduces the pressure (current) of the flow. Placing your thumb over part of the end of the hose reduces the size of the opening (voltage) and increases the pressure of the flow. Voltage is INVERSELY PROPORTIONAL to current!

Enuf physics... The answer to your question is simply - YES, increasing your voltage WILL hurt devices needing a specific voltage (I am assuming you are talking about increasing voltage within the power supply where there are tons of warnings saying that adverse things can happen if you muck with stuff - gorilla mentality) and will reduce the current capacity of the power supply. If you're wanting to increase voltage using jumper settings on the motherboard, READ a BOOK about motherboards and what that jumper is for! You can destroy your CPU! - FRIED, CRISPY CRITTERS! Yup-Yup, deader'n a doornail.

But, to attempt to answer you're unspoken question about your power supply's capacity...

Now, if you have the specs for each of the devices plugged in THE MACHINE, you'll need to determine the CURRENT needs (or draw) the manufacturer expects out of each device, add them all up (don't forget the fan(s), they suck quite a healthy amount too!). If the total is anywhere near 75% of the maximum calculated above, you are overtaxing your power supply and really need to seriously consider getting a bigger Power Supply.

As a general rule, a monster video card, a CD, 2 HD's, whopping bunches of RAM, a NIC, an internal modem on OC'd CPU sporting a general 235W power supply is just about maxxed. Adding that 2nd CD or CDR/CDRW will push it over the limit, or adding a SCSI card and any internal SCSI devices will exceed the power supply's ability.

Don't monkey with THE VOLTAGE unless you're willing to suffer the consequences and potentially lose at the least - your CPU. Know your subject!

-- Then have fun /forum/smile.gif

Laz

[Roy]

LazMan presents a nice treatise on electrics.

You don't say what the power rating of your supply is. The ATX standard requires a minimum 235W PS. Mid tower cases usually give you 235 or 250W supplies. Full tower cases usually have 300W units. It has to do with the number of drive bays.

CPUs need about 40W. A loaded mobo with a serious video adapter might need 150W total (including CPU). Allow 15W for each drive. Fans take very little.

I'd say you're on the edge with a 235W PS. 250 would be safer.

[Mitch]

Wow! Way to go LazMan and Roy..These are two of the best and right on answers I've seen in alot of forums...Keep it up...Mitch