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der8auer

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Looks like the clock chip? or something thats there normally? is missing though, is that normal for volt mod or

 

Not sure what the mod is after a second look but that solder point looks to be for a oscillator crystal and it may or may not have had something there before

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  • 6 months later...

NCP5388 is one of the "evil" pwm ,not many can manage to pass over his OVP:D

 

FB is pin19 , at ~ 1.3v ocp will trigger , if you lowering in half the ressistance between ILIM (pin 12)and ROSC(pin12) you will earn another ~50mv , till OVP will trigger ...and game is over!

 

when you see NCP on the card´s zombified them quickly :D

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NCP5388 is one of the "evil" pwm ,not many can manage to pass over his OVP:D

 

FB is pin19 , at ~ 1.3v ocp will trigger , if you lowering in half the ressistance between ILIM (pin 12)and ROSC(pin12) you will earn another ~50mv , till OVP will trigger ...and game is over!

 

when you see NCP on the card´s zombified them quickly :D

 

In the datasheet for the NCP5388 it says that the ILIM pin:

"Over current shutdown threshold. To program the shutdown threshold, connect this pin to the ROSC pin via a resistor divider as shown in the Applications Schematics. To disable the over current feature connect this pin directly to the ROSC pin. To guarantee correct operation, this pin should only be connected to the voltage generated by the ROSC pin – do not connect this pin to any externally generated voltages."

 

So if you short ILIM(pin 13) to ROSC(pin 12) it should disable OCP.

 

Here's the datasheet:

http://www.onsemi.com/pub_link/Collateral/NCP5388-D.PDF

 

On the topic of OVP it says:

"The OVP circuit monitors the output of DIFFOUT. If the DIFFOUT signal reaches 180 mV above the nominal 1.3 V offset the OVP will trip. The DIFFOUT signal is the difference between the output voltage and the DAC voltage plus the 1.3 V internal offset. This results in the OVP tracking the DAC voltage even during a dynamic change in the VID setting during operation."

 

The thing is I don't see how the NCP5388 could possibly know what voltage the VRM is putting out if you go and mod the VS+ instead of VFB. Admittedly VS+ goes straight to VCC but I bet you can cut the trace for it somewhere and then feed it a skewed voltage reading through a potentiometer to get the voltages that you actually want.

 

That's what I would try before going full zombie at least.

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In the datasheet for the NCP5388 it says that the ILIM pin:

"Over current shutdown threshold. To program the shutdown threshold, connect this pin to the ROSC pin via a resistor divider as shown in the Applications Schematics. To disable the over current feature connect this pin directly to the ROSC pin. To guarantee correct operation, this pin should only be connected to the voltage generated by the ROSC pin – do not connect this pin to any externally generated voltages."

 

So if you short ILIM(pin 13) to ROSC(pin 12) it should disable OCP.

 

Here's the datasheet:

http://www.onsemi.com/pub_link/Collateral/NCP5388-D.PDF

 

On the topic of OVP it says:

"The OVP circuit monitors the output of DIFFOUT. If the DIFFOUT signal reaches 180 mV above the nominal 1.3 V offset the OVP will trip. The DIFFOUT signal is the difference between the output voltage and the DAC voltage plus the 1.3 V internal offset. This results in the OVP tracking the DAC voltage even during a dynamic change in the VID setting during operation."

 

The thing is I don't see how the NCP5388 could possibly know what voltage the VRM is putting out if you go and mod the VS+ instead of VFB. Admittedly VS+ goes straight to VCC but I bet you can cut the trace for it somewhere and then feed it a skewed voltage reading through a potentiometer to get the voltages that you actually want.

 

That's what I would try before going full zombie at least.

 

i tryed that few years back and only way is VID mod no other way , that way i vid moddded my all cards directly when OVP trip , that is the ONLY WAY to aviod ovp:D

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Yes, true. All/most custom Gainward and Asus PCB use one of these NCP controllers and the only way is VID mod. Probably others too, but that's what I had.

It's not that hard and in most cases you don't want to support all possible VIDs anyway. Sometimes not all VID pins have exposed resistor, they are just grounded.

Maybe there's another way, but this is the most reliable one. After VID-modding the card there's no OVP anymore on the ones I've modded.

Edited by I.nfraR.ed
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Given it has 8 vid pins I'm guessing it uses the vr11 vid table shown here https://www.google.com.au/url?sa=t&source=web&rct=j&url=http://www.intel.com/Assets/en_US/PDF/designguide/321736.pdf&ved=0ahUKEwiG6MCyv_jQAhVQtJQKHdCtBIkQFggZMAA&usg=AFQjCNEI-oZwSVf5jo5KHV4bKHHLxvWAfw&sig2=ZT_-yj8HBe42eyVjs1Zfvg

 

Cross reference the stock voltage of you card to this table and see if it matches the VID pins shorted on the card

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Given it has 8 vid pins I'm guessing it uses the vr11 vid table shown here https://www.google.com.au/url?sa=t&source=web&rct=j&url=http://www.intel.com/Assets/en_US/PDF/designguide/321736.pdf&ved=0ahUKEwiG6MCyv_jQAhVQtJQKHdCtBIkQFggZMAA&usg=AFQjCNEI-oZwSVf5jo5KHV4bKHHLxvWAfw&sig2=ZT_-yj8HBe42eyVjs1Zfvg

 

Cross reference the stock voltage of you card to this table and see if it matches the VID pins shorted on the card

 

I'm gonna check it

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  • 1 month later...

Hey guys! I'm Duality92 from Overclock.net. I'm trying to figure out something new and if one can figure it out, it could possibly mean new heights with FM2+.

 

As we all know, FM2+ is limited with it's TDP. Could we eliminate this with a mod? I've opened up a thread on Overclock.net, but I will post all relevant information and pictures here.

 

Now, like shunt mods on graphic cards, can I do this on my board? If so, what do I need to do? I want to achieve new heights with this platform. Is an actual volt mod needed?

 

 

Motherboard

http://imageshack.com/a/img922/4341/G0tODf.jpg

 

Controller

http://www.infineon.com/dgdl/pb-ir3567b.pdf?fileId=5546d462533600a4015356803a7228ef

 

IR3567B - Infineon Technologies

 

Controller placement

http://cdn.overclock.net/a/aa/aa5ad562_IMG_20170118_065112.jpeg

 

Controller pin layout

http://cdn.overclock.net/2/22/22f53145_3567B.png

 

Back of the motherboard (to show there isn't anything very relevant)

http://cdn.overclock.net/a/ae/ae9911be_IMG_20170118_065230.jpeg

 

*Note* Rules request that I host the picture here, but there isn't any options for me to upload anything.

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Fm2+ is most definitely not tdp limited as I've run it at 1.8-2v with all cores running cinebench without a issue

 

If you are having problems with tdp it should have an option to disable it the bios unless you are using something like the athlon 845 which is tdp limited no matter what

 

The F2A88XN-wifi is one of the best fm2+ boards I've used and it doesn't any issues running 2v+ under load as it has extremely high end power delivery on the cpu/nb despite being 4+2 phase

Edited by newlife
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I'd like to send you a PM, but it seems I can't. Not sure if it's because I'm "new" here or if it's the forums, so I'll just ask here.

 

Fm2+ is most definitely not tdp limited as I've run it at 1.8-2v with all cores running cinebench without a issue

 

If you are having problems with tdp it should have an option to disable it the bios unless you are using something like the athlon 845 which is tdp limited no matter what

 

The F2A88XN-wifi is one of the best fm2+ boards I've used and it doesn't any issues running 2v+ under load as it has extremely high end power delivery on the cpu/nb despite being 4+2 phase

 

Wow, that's great news, I didn't even know. I'll be running a modded BIOS along with 2400/10 Samsung HYK0 Trident X (2*8GB) on this board.

 

Since CPU is under water with a 280mm XT45, what kind of voltage to do you think I can run safely? (coming from a guy who runs his 6600K at 1.488V load 24/7). 1.55? 1.6? I'll figure out the rest when I get this under water :)

 

edit : you can send me a PM on Overclock.net if you wish :) (user Duality92)

Edited by dualityyy
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  • 2 months later...

Hi,

Idk, if this still active, but this seems like my best shot. I got custom quadro k4000, won from a competition. Which is really weird card, because it has 4 gigs of vram (instead of 3 gigs) has no external 6 or 8 pin (casually has 1 6 pin). I've found out that it uses NCP81172 from semiconductor as pwm controller. Got datasheet and where is feedback pin on pcb. It seems like it has two resistors and one capacitor connected. I'm not sure where to put my potentiometer. Also found shunt resistors, where im gonna put an molex connector to increase power and I think it considered as pcie power in bios. Correct me on that if im wrong. It would be really nice if someone can help me with it. I attached datasheet and common application and also photo of pcb. All in all this seems doable but im really new in computer stuff but im good with electronics so got pretty good soldering skills.

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Either you have the wrong pwm or soldering to wrong place or fb just doesn't work but VID mod should work as you just need to short vid pins based on table in datasheet (conductive pen/liquid metal will work or even a DIP switch for easy adjustments)

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  • 9 months later...

This thread is a bit quiet. :P

 

Anyone have access to the VT235WF datasheet?

 

I need it for memory voltage control on my GTX 260 216sp 65nm card.

 

Thanks in advance.

 

Edit: that's the mosfet apparently. (facepalm)

 

It was the only thing which looked like a controller other than the VT1165 on core.

 

But apparently this is the GTX 280 PCB and there is no visible mem controller.

 

image_id_1963711.jpeg

Edited by Noxinite
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