# Thread: Whats dependent on the 5.5 rail?

1. ## Whats dependent on the 5.5 rail?

Im trying to figure out whats dependent on the 5.5 rail.. Since im not too sure exactly. >>

Ive been expermenting with this old Dell psu I had, taking it apart and lo and behold, I find a potentiometer that controlls the 12 rail, I get that up 12.5 (Using a DMM)with no problems but come to find out, the 5.5 is actually quite low. On a DMM with nothing hooked up, it reads out 5.3 and theres no pot for that.

..Rambling.

Know what, what does each rail go to? Lets just make it as simple as that.

2. Originally Posted by Reznik Akime
Im trying to figure out whats dependent on the 5.5 rail.. Since im not too sure exactly. >>

Ive been expermenting with this old Dell psu I had, taking it apart and lo and behold, I find a potentiometer that controlls the 12 rail, I get that up 12.5 (Using a DMM)with no problems but come to find out, the 5.5 is actually quite low. On a DMM with nothing hooked up, it reads out 5.3 and theres no pot for that.

..Rambling.

Know what, what does each rail go to? Lets just make it as simple as that.

12V=Cpu/Current Vga's/Fans/Cathodes/HD's/CD-RW-DVD/ etc.....
5V=Old Cpu's/Radeon Series/Usb/HD's/CD-RW-DVD/ etc.....
3.3V=Ram/Vga Ram/Chipsets NB&SB

3. so the 5.5v is for molex's

4. here i got this table its not that simple as somethings only uses one rail

5. There is no such thing as a 5.5 rail. There are these: 12V, 5V, 3.3V, GND and not so much anymore, the -12V and -5V rails.

6. Thats right.. Not 5.5 but straight five. I dont know where I got that number. Thanks for clearing things up though.

Anyway, whats a safe voltage for the 12v line?

7. Originally Posted by Reznik Akime
Thats right.. Not 5.5 but straight five. I dont know where I got that number. Thanks for clearing things up though.

Anyway, whats a safe voltage for the 12v line?
12V=12.60V
5V=5.25V
3.3V=Infinite

8. the +12v rail should be @ 12v +/- 5%. But you want as little change as possible. So ideally you want 12v.

9. Hmm.. Ive seen people keeping it at 12.5 24/7 with no issues. Ill stick it up to 12.6 for good measure. >>;

10. My benching setups regularly run the 12V rail at 13V and the 3.3 rail at over 4V. The 5V rail kinda gets ignored, I usually only push it up to something like 5.2V.

11. Has there been any documented cases of components blowing, other than the PSU? Say the hard drive or cd drive or anything?

12. Originally Posted by Reznik Akime
Has there been any documented cases of components blowing, other than the PSU? Say the hard drive or cd drive or anything?

yes, but it depends on the quality of the psu, bad quality can kill many things if you up de rails, if it is a good quality psu it shouldn't kill anything

13. It must be good quality. I never expected this kind of performance out of a heavily used 3 year old Dell psu. Its only 250w and its already a HELL of alot more stable than that Xion crap 400w was, and when I first plugged it up, the voltages have always been set to 11.85 it seems. Thats what it was before I had started tweaking the volts.

I tested it before I tweaked and I never got the BSOD in games anymore. Im also able to get better memory clocks. Before I couldnt even run my memory at DDR403 without a slew of errors, now its at 410 and burning its way higher.

Although I do think that 173x21 is my Cores maximum. No better overclock there.. Just more stable.

14. Originally Posted by Reznik Akime
It must be good quality. I never expected this kind of performance out of a heavily used 3 year old Dell psu. Its only 250w and its already a HELL of alot more stable than that Xion crap 400w was, and when I first plugged it up, the voltages have always been set to 11.85 it seems. Thats what it was before I had started tweaking the volts.

I tested it before I tweaked and I never got the BSOD in games anymore. Im also able to get better memory clocks. Before I couldnt even run my memory at DDR403 without a slew of errors, now its at 410 and burning its way higher.

Although I do think that 173x21 is my Cores maximum. No better overclock there.. Just more stable.
I remember having 2 of these 250W dell psu your talkin bout. Yup they are well built but gets very hot when tortured. It had 3 pots iirc, 1 is for fan control and 2 is for 3.3V and 5V/12V etc....This things also had rubycon capacitors all over the place If you happen to take a peek again check the labels on the caps. I'm sure you'll see a couple of rubycons in there even the big one

15. em...arent dell powersuplies inverted?

16. Originally Posted by AKURA
I remember having 2 of these 250W dell psu your talkin bout. Yup they are well built but gets very hot when tortured. It had 3 pots iirc, 1 is for fan control and 2 is for 3.3V and 5V/12V etc....This things also had rubycon capacitors all over the place If you happen to take a peek again check the labels on the caps. I'm sure you'll see a couple of rubycons in there even the big one
Im sure I will be soon. I have the case opened up with a large fan directly on the Heatsink. One hell of a shock hazzard.. But meh.

I wonder if anyone has docs on how to up the 3.3 and 5 voltages with them lovely potentiometers..

17. Originally Posted by Reznik Akime
Im sure I will be soon. I have the case opened up with a large fan directly on the Heatsink. One hell of a shock hazzard.. But meh.

I wonder if anyone has docs on how to up the 3.3 and 5 voltages with them lovely potentiometers..
Yeah, just be careful when tweakin the pots. You can max them if you want. They only go to 12V-12.22/5V-5.22V/3.3V-3.40V on those stock pots when I tweaked mine. Ground the unit if you can also, Gotta tell you bro while I was modding my 700W zippy I felt so dizzy and . I almost puked. Until now i'm still wondering how the hell did that happen. I probably didnt ground the unit well enough......Take your time.

18. Oh dont worry.. Ive gotten me a good shock before that I never wanted to experence again in my life. When working with Central Air and Heating caps.. BE CAREFUL AROUND THEM! Bastards will bite you HARD! ><

Made my ass roll back on the ground a few feet. My whole friggin body was numb and I had a scant burn mark on my finger where it reached out and touched me. Surprised it didnt kill me. Felt near like it though. x_x