How important is +3.3

[fluke420]

Since I have overclocked my 2.4C I have been watching Motherboard Monitor more and more. One thing I have noticed is the +3.3 is around 2.5 under full load. Is this normal? Is it a power supply issue?

Power wise its a Enermax 350w, 3 80mm, 1 120mm, 4 normal WD 20G, 1 normal CDRW, and a Zalman.

Is this too much for a 350w power supply?

Could the 2.5 be the reason the computer is not prime95 stable?

 

[reflex33]

Those 4 HDs are not helping the matter. But yes a 350w may be a little underpowered. When a power supply gets near its limit on power, the voltage tends to drop which keeps the power in check, but also makes things unstable.

I would look at getting a 431w or 450w Enermax or Antec.

 

[fluke420]

Thanks for the help. One more question.

Does the voltage drop across the board? Meaning -12, +12, +3.3 etc? My Vcore is all over the place.

 

[heyheyhey]

get a PP&C. the 510 ATX deluxe is about the best you'll get. comes sleeved and everything. www.pcpowercooling.com theres the link.

 

[fluke420]

That's a very nice PSU but I do not have $180 to spend.

 

[techhed]

a hard-drive can use about 100-110watts. your cpu uses about 80-90watts. look into getting power supply from antec 400watt or above

 

[ChAotiCIllusion]

ermmm a 100 watt hard drive. I guess my 430W powersupply can't take the 5 drives connected to it. The max for a hard drive is normally 15 Watts. P=IV. My seagate I happen to have out takes 0.75A off +12V and 0.85A off +5V.
The 3.3V line is the normal supply for the motherboard and the RAM and is normally quite lightly stressed. If you can borrow a PSU from a friend and test, if it's still unstable it's possible you just have a poor clocking chip.

 

[md262626]

Originally posted by techhed
a hard-drive can use about 100-110watts. your cpu uses about 80-90watts. look into getting power supply from antec 400watt or above

A HDD does not consume 100-110 Watts of power. About 10-15 watts is the correct figure for a HDD in the 80 GB range, figure 20 watts for a HDD > 80 GB to be on the safe side. The following was taken from PC Guide: http://www.pcguide.com/ref/hdd/perf/perf/spec/otherPower-c.html

 

[techhed]

his 4 HDDs could spike that high. according to this chart http://www.tomshardware.com/howto/20040122/power_supplies-04.html

 

[batotman]

Ok LISTEN to me. 350W is enough, i don't care what these guys say or think, I've been through it enough times to know its plenty, I ran my rig with 350W Enermax and went to a 430W Enermax thinking hmmm these guys think a bigger PSU may increase my overclock.....wrong. I run a Nforce2 board at work on a 200W Liteon.

But back to your question, just because mobo monitor says something does not make it fact. You would have to measure yourself to get an accurate reading (no software crap).

I believe your CPU is topped out. Your sig states 3.33Ghz assuming this is the same processor thats a good overclock. I can run mine at 3.4 but choose to run it at 3.2 because I don't like increasing the voltage.

 

[reflex33]

Originally posted by fluke420
Thanks for the help. One more question.

Does the voltage drop across the board? Meaning -12, +12, +3.3 etc? My Vcore is all over the place.

It could lower the voltage across the board, but it depends on where the power is being drawn from.

Power supplies are not rated at 431w or whatever meaning they can supply that much power to any one rail. It means that the sum of all rails equals 431. For instance, if the 12 volt rail can handle 100w and the +3.3v rail can support 100w, then thats 200w, not 200w to just any one of those rails.

So if your hard drives are drawing all their power from the 5v line, then that line is the one that will start to fall. But under load like form Prime95 all the lines are put under stress from different componets.

The best overall solution is to get a better power supply that would raise the power available to each rail.