3.3, 5.00 and 12v modding

[AcEmAsTr]

my voltages are... to put it lightly....§§§§, right now my 12volt is at 11.61, 5volt is 5.03 and 3.3 is 3.22,...


i have a Qtec dual fan 400w psu and would like to od my rails up to about 3.4-5 and 5.2-3 and 12.3-4, does anyone have a newbie guide to doing so? im kind of knowledge impaired when it comes to electronics.




Thanks

[Asio]

Its 3 treads below yours
http://www.xtremesystems.org/forums/showthread.php?s=&threadid=14059

It doesnt aply on the antecs only but on every psu that has sense wires

btw. have there bin case of hardware diying because of to high rails and what benefits does having your rails higher then +10% have as mine are already @ 3.55, 5.5 and 12.8?

[AcEmAsTr]

Originally posted by Asio
Its 3 treads below yours
http://www.xtremesystems.org/forums/showthread.php?s=&threadid=14059

It doesnt aply on the antecs only but on every psu that has sense wires

btw. have there bin case of hardware diying because of to high rails and what benefits does having your rails higher then +10% have as mine are already @ 3.55, 5.5 and 12.8?


i fail to see whature saying, but id like my rails a touch higher just so it stables everything out...


i see ure post as saying that hardware can die when rails get too high, but u state yours are so much higher

[Hell-Fire]

To much voltage is bad for anything, that being said, you can run 12.75v, 5.75v, and 3.75v without a single issue. Just be certain that your psu fans are cooling good enough. If you stick your hand on the exhaust fan after the mod and the air is farily warm, better change the fans out.

Do this, take a pic of the ATX connector from a few angles so that we can see the wires going into the 4 corners of it. Then maybe we can go from there.

Here are some pics of the last mod I did on a psu:

Snipped sense wires and soldered a 47ohm fixed resistor between the 2 leads.
http://www4.ncsu.edu/~rwbradl2/CSC251/images/FixedResistor_3.3.jpg

Here I soldered a wire to the top leg of the fixed resistor, and it runs to the middle leg of my VR
http://www4.ncsu.edu/~rwbradl2/CSC251/images/FixedResistor_3.3_single.jpg

What I used for grounds is molex connectors I snapped off a dead psu. Soldered them to top leg of VR and plugged them into a fan molex connector on the psu.

http://www4.ncsu.edu/~rwbradl2/CSC251/images/Grounds.jpg

http://www4.ncsu.edu/~rwbradl2/CSC251/images/Grounds2.jpg

http://www4.ncsu.edu/~rwbradl2/CSC251/images/GroundsPlugged.jpg

http://www4.ncsu.edu/~rwbradl2/CSC251/images/New12.jpg

http://www4.ncsu.edu/~rwbradl2/CSC251/images/New5.jpg

http://www4.ncsu.edu/~rwbradl2/CSC251/images/New3.3.jpg

[Asio]

And does increasing the 5v line put more stress on the mosfets?
So if u run 2V+ vcore they can get really hot (hotter then 5@5.4)?

And thus making the Vcore instable at high vcores or will the difference not be noticeable?

Thx for cooking up that mod btw :toast:

[blinky]

how do you do this for the 5v and 12v when theres no sense lines on them and no internal pots.

[skate2snow]

hell-fire: do you have a guide and the 12V, i need one? THX

[lalPOOO]

Originally posted by blinky
how do you do this for the 5v and 12v when theres no sense lines on them and no internal pots.

I think there are mods for some boards for increasing the rails, but if you can't find one, the answer might be ' you don't ' I don't mean to discourage you though from trying to find out, just that it'll be a bit more work.

[Tilmitt]

Hell-Fire, do you just need to put a 47ohm resistor straight onto each sense line and thats the modding done?

[Hell-Fire]

Originally posted by Tilmitt
Hell-Fire, do you just need to put a 47ohm resistor straight onto each sense line and thats the modding done?

No, you then have to solder a wire to the top leg of the 47ohm resistor. That wire goes to the middle leg of the variable resistor. The top leg of the variable resistor then goes to a ground point.

Some power supplies dont need the fixed resistor (47ohm) to work. For some reason its a required thing on the Antec series.

You can add just the 47ohm, but it wont affect voltages much at all.

[Hell-Fire]

Originally posted by blinky
how do you do this for the 5v and 12v when theres no sense lines on them and no internal pots.

You then have to find out which resistor on the power supplies pcb is responsible for it.

Some power supplies are modded with removing the R82/R83 resistor (think thats an Enermax mod), but not certain.

[Hell-Fire]

Originally posted by skate2snow
hell-fire: do you have a guide and the 12V, i need one? THX

I dont have a guide other than reading threads about it.

On almost all power supplies that have sense lines, you can do the mod easily.

If there is an internal pot, just change it out with a higher rated one to grab more voltage.

If the power supply has only one sense line for either the 12v or 5v rail, then modding that sense line will effectively mod both rails. Lowering the resistance on that VR will raise the voltage on both the 12v and 5v rails.

Be aware that I have recently come across ATX connectors that do not have sense wires solely on the corners of the ATX Connector as is standard. Most of the time you will see the 3.3v, 5v, and 12v rail feed wires at 3 of the 4 corners of the connector that goes into the motherboard. Alot of the time you will also see a thinner wire, this is the sense wire. So, no sense wire present means you have to hope for an internal pot or already know what internal resistor you need to remove/replace/parallel. BUT, some companies have recently started putting the sense wire in the middle of the ATX bundle.

I have read over the data sheet for a particular power supply and am going to attempt to mod the sense wire I found. If all goes well and the mod works, it should raise voltage on both the 5v and 12v rails. If so, then I will post a short guide to it. Its a sense wire for the 5v, which is typical for psu's that have only a single sense wire for both the 12v and 5v.