What does the 3.3V rail feeds?

Viperoni

Lifer
Jan 4, 2000
11,084
1
71
CPU is mainly driven off the +5 and +12v, P4's practically exclusively off the +12v.
IIRC The +3.3v supplies the videocard, RAM, NB/SB, etc.
 

ViRGE

Elite Member, Moderator Emeritus
Oct 9, 1999
31,516
167
106
The standard motto when it comes to power is that if it's off by 5% in either direction, you have problems. Since that would put the low floor for 3.3v at 3.135v, I'd say that could very well be an issue.
 

xenos500

Senior member
Jul 22, 2003
354
0
0
I dont think I have ever heard of the CPU using 3.3v lines. The CPU doesnt get any direct power from the PS anyways, The CPU voltage regulator is fed 12v from the PS and then the actual voltage of the power the CPU uses is carefully controlled.

3.3v is used by hard drives...in conjuction with the 5.0v, AGP cards, many PCI cards.

If you are seeing a lack of power, spare yourself a lot of problems and buy a new power supply. I think tomshardware does the best powersupply testing/reveiws. Check it out and decide on a new powersupply.

I went with Enermax because of their implementation of ATX 1.3, if that doesnt matter to you....I would suggest an Antec TRU POWER.
 

niggles

Senior member
Jan 10, 2002
797
0
0
I also have been having issues in the past couple of days with my 3.3 volt... it's fluctuating quite rapidly... goes from 3.10 down to 2.9.... obviously this is bad from what is being said above. My laptop got fried the other day as well and they both go through a UPS. I think it's safe to say that the UPS has to go (it's an APC), but would everyone agree that the first thing to check on the PC is the Power supply, might it not be the mother board?