R5E10 - Broadwell-E - What is VTT (CPU I/O Voltage)

[dialsc]

Hi,

while having fun with overclocking and reading a lot about it, I very often read about VTT which seems to be known as CPU analog/digital I/O voltage. I wonder if this is something that is available for a i7-6850K - Broadwell-E processor because I cannot find anything that looks like the tweaking screw for this one in the BIOS of the Rampage V Edition 10.

Could someone please try to help me getting an understanding about this?

Thanks and greetings.

dialsc

[Arne_Saknussemm]

VCCIO CPU on this platform...I've never had to touch this....works fine on auto

"Keep 0.05 less than VCCSA" from this guide http://edgeup.asus.com/2016/06/17/broadwell-e-overclocking-guide/5/

[dialsc]

Hey, you made my day. Thank you so much!

Please allow me to ask one or two more questions if you don't mind. They are:

• The value in the BIOS is VCCIO CPU 1.05V Voltage, isn't it?
  
• The "keep it 0.05 below VCCSA". Does it mean to keep it exactly 0.05 below it or at least and it could be even further away from the VCCSA?
  

[Arne_Saknussemm]

dialsc wrote:
The value in the BIOS is VCCIO CPU 1.05V Voltage, isn't it?

Yep...that's the one...

dialsc wrote:
The "keep it 0.05 below VCCSA". Does it mean to keep it exactly 0.05 below it or at least and it could be even further away from the VCCSA?

The guide says by keeping it about 0.05 below VCCSA is often sufficient to stabilize memory but also says it is not necessary to increase as much as VCCSA.

And in my case though I am on Haswell E VCCSA is less than 0.9v....so less than VCCIO and everything works fine...so...

Like I said I haven't found it necessary to play with this voltage for the 32GB 3200 MHz RAM I run. Even OCing and tightening timings....depends on your IMC (memory controller on CPU) as always I guess...

[dialsc]

Excellent, that helps me so much. Again thank you!

It might be different for me because as you said, every IMC is different and I've got a 128GB 3200 MHz RAM kit installed. I will come back and report if once I found I need to tweak this setting. Until then I will let it run on Auto.

dialsc

[Mappi75]

Arne Saknussemm wrote:


The guide says by keeping it about 0.05 below VCCSA is often sufficient to stabilize memory but also says it is not necessary to increase as much as VCCSA.

Does this mean my settig is wrong?

My system Voltage is 0,865V

VCCIO CPU is 1,05V

Then i will have problems?

You mean that my system Voltage should be 1,1V and then VCCIO CPU with 1,05V is correct? (max -0,05V).

But atm my 128GB DDR4 2.666Mhz Kit @1,20V runs stable with Prime95 v266

[Arne_Saknussemm]

Mappi75 wrote:
Does this mean my settig is wrong?

No I reckon you are fine.

That guideline is for getting memory stable if you are having problems and need to tweak voltage...

Vcore and VCCSA are the top voltages to concentrate on first...

I use RealBench for all my OC testing...much more holistic/system wide test....and kinder to the CPU with current draw...

[Arne_Saknussemm]

Nah, you're welcome!

Let us know how you get on 🙂

[Mappi75]

Hello,

can you explain which Voltages you also rise to run your 128GB Kits stable?

I own the Kingston 128GB DDR4 2666Mhz and rise the voltage from 1,20V to 1,22V.

Before that i got sometimes a driver less or equal error...but i dont know if i have to rise some other voltages.
I did not OC my cpu yet it runs only @ 3Ghz. (i want to get the system stable first).

BTW: got a gtx titan black sc 3-way-sli

Thanks

[dialsc]

Hi,

Sure, before I started to overclock the system I invested a lot of time to get the default settings with XMP enabled running. I did this in three step and tested and recorded each of them in detail. I can share this with you so here we go...

1. Defaults with XMP enabled and minimum DRAM adjustments.
First I loaded the BIOS default, then I enabled XMP and finally I made the minimum adjustments to get the kit running at its specification. All the settings and tests plus the results can be found here: http://office.das-online.org/oo/sharing/0ff725010c8943c59be9bbc993dbdd5d

2. Take the Auto settings and apply them manually
I then tried to configure the BIOS as manual as possible applying the values choosen by the BIOS in step 1. The tests, results and settings can be found here: http://office.das-online.org/oo/sharing/b42beb4bc0254c0fa7ee8fafc2e15e68

3. Minimum voltage settings required
Finally I tried to bring down all the voltages choosen by the BIOS in auto settings to their minimum values. The outcome of this can be found here: http://office.das-online.org/oo/sharing/c79134c72b0845929270d2d438517796

-------------------------

Right now I'm in the process of getting this machine running at 4400MHz @ 3600MHz cache. In case you are interessted in all the setups, test, results asf. you can take a look here: http://office.das-online.org/oo/sharing/26a6e7f50e5e4d4385ace0ae018c59df

I hope that helps you.

Greez,

dialsc

EDIT: Forgot to tell you what hardware I've got:

CPU: i7-6850K
RAM: G.SKILL F4-3200C16Q2-128GTZKW
GPU: PNY NVIDIA QUADRO K4200