PSU's 3.3v Rail directly connected to/as vdimm

[amilian]

I have thermaltake copper ramsinks on them, I don't see how I can have a fan blowing on them....

Attaching a fan over ram is pretty easy: rubber bands!
check this thread out.
http://forums.extremeoverclocking.co...d.php?t=113513

[amilian]

I have a few questions.
How are you guys gettings 3.6 and above with your psu's, I have an antec with the pots that I can adjust but I can't get more that 3.33.
I did the mod on my MSI neo 2 and it works awesome...but I need more voltage, I am stuck at 250 fsb right now with 2,2,2,5 1:1 timings.
Did we ever figure out how to use the 5 volt rail? because my bh-5 is screaming for some 3.6+ volts
Thanks
Bryan

not sure if having pots throws a spanner in the works, but here's one psu mod guide:
http://www.bleedinedge.com/guides/ps...v_mod_pg1.html
I did it and can take my 3.3 rail up to 38v before it craps out...
Hey, can you post a pic of your mod with the neo2? and was it the platinum?
EDIT: Here's another good guide
http://forums.extremeoverclocking.co...ad.php?t=97195

[moparacer]

Will this mod work on a DFI lanparty pro 875B mobo? Anyone try it? It worked so good on my 4PCA3+ a friend of mine wants to mod his DFI..... The lanparty only goes to 2.9 vdimm just like my Epox did......

[All4AMD]

i think ill make myself a voltage regulator off the 5v rail and send 3.6 to the memory or if i can turn the rail on my Antec480 True blue psu just do that

[Gautam]

I have a few questions.
How are you guys gettings 3.6 and above with your psu's, I have an antec with the pots that I can adjust but I can't get more that 3.33.
I did the mod on my MSI neo 2 and it works awesome...but I need more voltage, I am stuck at 250 fsb right now with 2,2,2,5 1:1 timings.
Did we ever figure out how to use the 5 volt rail? because my bh-5 is screaming for some 3.6+ volts
Thanks
Bryan

Want to hear some more about this as well. I've had a direct +3.3v mod for months. Now I'd like more. Should be able to put +3.3v rail at about 3.65v, but I'd prefer closer to 4v if possible. Anyone got the the +5v rail reduced successfully?

[moparacer]

Update on the DFI lanparty pro 875B rev. B1 mobo.....

Went ahead and tried it tonight and it works but max vdimm measured at back of mobo can only be set to 3.28 max to be safe (adjustable 3.3 rail PSU) as OVP kicks in at 3.30.....


Can Rio or ANYONE help me with disabling the overvoltage protection for the vdimm on this board? Man if I can get that accomplished I will be happier than a pig in the mud!

[choseone214]

Originally Posted by rabeb25
I have a few questions.
How are you guys gettings 3.6 and above with your psu's, I have an antec with the pots that I can adjust but I can't get more that 3.33.
I did the mod on my MSI neo 2 and it works awesome...but I need more voltage, I am stuck at 250 fsb right now with 2,2,2,5 1:1 timings.
Did we ever figure out how to use the 5 volt rail? because my bh-5 is screaming for some 3.6+ volts
Thanks
Bryan

Cut sense wire "small orange that runs with fat orange" to molex and add a 10 ohm 1/4w resistor in line. Next the side of the resistor thats closer to the psu solder a thin wire and connect that to a 10k ohm VR and ground the VR to the psu's ground. Set VR at 10k to start set front panel on antec to max 3.3-3.42v and then adjust this 10k until you get to about 3.65-3.75v. Now with front panel you should have a high of 3.65v and a low of about 3.3v enjoy.

[Lord_RTKK]

How about doing this 3.3v mod to an Abit KV8 Pro 1.1??
Help me a bit, I can post pictures of this mobo if you can tell me where to solder...

P.D.
Excuse for my bad english...

[persivore]

I have designed/built a regulator which allows the 5v line to be be adjusted between 0-5v. I will draw up and post the circuit diagram if anyone is interested in it. I am using the regulator on my NF7-s and it appears to work well.

[STEvil]

Please do

[persivore]

circuit diagram
The circuit uses a LM358 OPAMP, which should be powered from the 12 volt line, so will priovide a maximum of about 10v which is enough voltage to be able to fully turn on the MOSFET. The +'ve pin (which should be connected to +12v) is pin 8 and the -'ve pin (which should be connected to ground) is pin 4. The LM358 is a dual OPAMP, with the other half being left unused. The IRF540 MOSFET is rated to about 100w iirc, so should be able to provide enough power for RAM as long as it has an adequate heat sink on it.

[STEvil]

100w is a bit low... is that rated with or without heatsink?

[persivore]

I think it is rated with a heatsink. I worked out that it *should* be able to supply 5v@20 amps and 3.3v@30 amps as long as it is cooled properly, so it should be enough for most RAM

[STEvil]

heh.. my 2x512 of CH-5 will eat up 1 amp per chip.. thats 32 chips TCCD are known to pull even more than BH/CH..

It might be enough, but I think we'd be stretching it pretty thin by running TCCD or BH/CH at high clocks.. and ramping up the volts could push it past its limits in a real hurry.

[persivore]

Most of the power supplies I have seen are rated to about 30amps on the 3.3v line. If you do the Vio=Vdimm mod and the RAM used that much power I would expect the power supply to shut off due to OCP. Also, I doubt that the thickness of the cable that I have seen used in the Vio=Vdimm mod could supply 30 amps without melting. However, if you want to be able to supply massive currents to your RAM, a different MOSFET such as the HUF75337P3 which is rated to 60amps+ could be used. I would advise against drawing that much power from a PSU tho!

[cain1234]

hi, I want to do a vdimm mod on a 8kda3i mobo, all i have to do is soldering a wire between the 3.3v rail and some pin on a dimm slot? but what pin? could you tell me? thanks !

[STEvil]

I agree persivore, and I know each chip is not under full load all the time.. thats why we dont see them tripping out and wires catching fire.. heh.

Being that we regularly push equipment past its rated limits 100w might just be a bit close to the edge with 2x512 at high mhz with a bunch of volts..

[cain1234]

???could you tell me what pin do i have to solder? 10q

[iddqd]

some day if i feel crazy instead of doing 3.3, i'll do the same with 5v

By all means, do it - I want to see results . The thing is, you get diminishing returns past 3.9vdimm - you have to raise vdimm by 0.1 to get another 2Mhz out of it. What I suggest doing is making an evaporator that will mount on a single-sided BH-5 stick. Running it at -90ish should do the trick to enable you to use 0-0-0-0 timings (everything happens statically!) at DDR500-550.

[bahadir_bado]

that looks cool , i will try it when my mobo comes

[Rio71]

Can Rio or ANYONE help me with disabling the overvoltage protection for the vdimm on this board? Man if I can get that accomplished I will be happier than a pig in the mud!

mmm... i dont know how it works and what circuit the ovp made..
if the mobo not in my hands.... i can't help you... so sorry, man..

[persivore]

Update on the DFI lanparty pro 875B rev. B1 mobo.....

Went ahead and tried it tonight and it works but max vdimm measured at back of mobo can only be set to 3.28 max to be safe (adjustable 3.3 rail PSU) as OVP kicks in at 3.30.....


Can Rio or ANYONE help me with disabling the overvoltage protection for the vdimm on this board? Man if I can get that accomplished I will be happier than a pig in the mud!

It might be possible to disable the OVP on the board. If you can post some pictures of the Dimm slot area, I might be able to help.

[kryz]

maybe had been already postet, but can anyone tell me, where to measure vtt on is7 ?

[desert_eagle]

Hi kryz,
I know the point to measure the VTT. You can see it on my picture.

[loopy83]

Sorry for using this old thread

Is this mod also available an a P4C800 Deluxe?

The easy version of the mod, is to locate Pin 7 of the dlots and connect it to the orange wire of the ATX connector?!
Does this version work with my mainboard? Or are there any other modifications necessary?

Cause of my bad english, i dont understand the whole VTT problem.... can somebody explain it in german or in easy english?

BR Loopy