Would you be comfortable with this overclock???

[Hoody_s13]

Hey peeps, I've been doing a little reading in hopes that I can optimise my overclock even further, maybe even push it a little more while keeping temperatures at a minimum.

I realised that load line calibration (LLC) was enabled on my board. It is actually set to Auto and I thought nothing of it, until I realised I was getting no vdrop/vdroop yesterday through CPU-Z.

 

Heres my current stable setup with LLC enabled, I tested this for quite some time a couple months back and couldnt drop my Vcore anymore.

 

980x @ 4448mhz 1.343v (LLC Enabled), QPI 1.25v, HT enabled

143blck, 31 Multi

2006mhz ram 9-10-9-27 2N @ 1.65v

On a warm day like today temps can hit 80-82 degrees under an IBT x 20 run, but generally dont rise over 75-77 degrees.

 

 

Anyway to the question, I tried disabling LLC and optimising my voltages again to stay on the safe side. I couldnt keep the same overclock stable with bios volts set at 1.375.

In windows with vdrop it displayed 1.356v idle, then vdroop under load dropped volts down as low as 1.290v, I get a 101 BSOD for more vcore. I cranked up the volts to 1.386v bios(around that), idle was 1.363v, load 1.312v, still BSOD.

 

With LLC, CPU-Z has never spiked higher than 1.356v, but I read you can have higher spikes that monitoring software can not read.

 

Am I safe to keep my current settings with LLC enabled for my 4.4ghz clock?

 

 

-Rhys

Edited March 22, 2011 by hoody_s13

[mattyamdfanboi]

so the voltage drops when u load it up.. what psu r u running???? . ones generally do that.. as they are unable to keep up the supply... :/

[Hoody_s13]

Yeah under load it drops volts without LLC on. I'm running a corsair ax1200, I thought this vdroop was a normal occurence?

[Alexandre]

Load line calibration is there to reduce v-droop (usually by a significant amount). By turning it off, you shouldn't be surprised to have a larger voltage drop...

[mattyamdfanboi]

how strange.. mine doesnt drop at all.. regardles of load.. it always stays at the same voltage..

 

 

oh wait.. is that an intel thing?

Edited March 22, 2011 by mattyamdfanboi

[Alexandre]

how strange.. mine doesnt drop at all.. regardles of load.. it always stays at the same voltage..

 

 

oh wait.. is that an intel thing?

I don't really know much about it (yet - I'm only second year Elec Eng) but it sounds like it would be related to CMOS transistor architecture found in a CPU and how the voltage drops when more transistors are under load.

Sounds like the CPU has a feature which calibrates the CPU load line so that the input voltage remains constant (or close to it).

 

Maybe AMD uses the same feature but it doesn't allow you to change settings I don't really know.

I do know however that it is a useful setting which will keep your voltage constant and stop your from having to raise your voltage through the roof at idle so your computer doesn't crash under full load.

There were fears that a sudden correctional change in CPU voltage would cause voltage spikes to occur but from what I have seen on the net, if you have a decent motherboard with good voltage regulation circuitry, then you shouldn't worry about them.

 

I would probably leave the LLC at Auto.

[Nuclear]

Vdroop or vcore drops are not caused by the PSU and are not dependent on AMD or Intel. Vdroop occurs in almost every board, it's just a matter of how bad the vdroop is. Higher quality boards with better power regulation for the CPU will see less of a vdroop problem. Boards with poor regulation or poor components will suffer from bad vdroop problems. Don't think just because your board says it has 8+ phase power that it will be rock stable either, because I have seen and tested many boards that claimed to have great regulation only to find out it was crap and couldn't hang with lower end boards. Also, don't always believe what your BIOS or windows program is telling you about your vcore. These sources can be very inaccurate and give a false sense of security. I always probe my boards with multimeter to ensure I'm getting the correct voltage and to measure the effective vdroop.

 

I tend to leave LLC off, simply because I don't like anything compensating for a poor power regulation system. I've seen LLC severely over volt processors and it makes them unpredictable in most cases when you are really squeezing the life out of a system.

[IVIYTH0S]

Leave LLC and I am so jealous since I get those temps with only 3.99ghz on a 920

 

It's a good thing, read here:

http://www.overclockers.com/load-line-calibration/

 

and here:

http://www.anandtech.com/show/2404/5

[mattyamdfanboi]

i dont know.. all i know that mine doesnt drop at all.. unless it goes into idle.. then it drops vcore and speeds.. otherwise it sticks at whatever voltage i say for it to stay at.. and doesnt drop .001

[l1o2l]

Thats Speedstep, the drop of vcore and speed.

[Hoody_s13]

Thanks for the info peeps!

 

Interesting read from Bobnova here, I'd like to borrow my mates multimeter and test the theory myself. The RE3 board I'm using has a number of testing points to pickup readings easily.

 

I think in my case reaching 4.4 ghz is only achievable using LLC enabled. I cant see this system remaining stable unless I push 1.375v or more through it at idle, so under load it wont dip down past it's stable voltage point.

Really not to keen on using the chip on or past its recommended max vcore, but interested too see if LLC throws larger spikes on my system past 1.375v.

 

I'll try grab that multimeter some time this week and post results on here.

Edited March 23, 2011 by hoody_s13

[wevsspot]

In this day and age I always recommend enabling LLC or low vdroop settings. Vdroop affects more than just your cpu voltage too. An example on socket 1366 boards is that vdroop can also affect QPI v which can cause overclocking stability problems too.

 

So to keep is simple - enable LLC, Load Line Calibration or Low Vdroop or whatever you particular motherboard bios calls it.