How to set up GTL Ref Values for 45nm & 65nm

[seban]

Hey guys

In my case seems that this chip or mobo likes negative GTLS...

I achieved to pass IBT at:

448x9 = 4032
vcore set 1,325 vcore idle 1,316
vtt 1,29
GTLS CPU +10/-50/+10/-50
pll 1,5
mems 1:1 (but tested on 1200 PL7 also pass IBT and 2500%MEMTEST)

IBT stable whenever i run it...BUT look this

450x9 = 4050
vcore set 1,325 vcore idle 1,316
vtt 1,2875
GTLS CPU +10/-45/+10/-45
pll 1,5
mems 1:1

I get it to pass IBT but today failed BSOD...then after some hours passed...again

Everytime i want to run on more VTT seems to be more unstable, also on positive GTLS BSOD comes faster
I'm kinda stuck on this, i want to start testing all over gain but really i don't know where to start on GTLS

I can also run it at 470x9 with low volts and i can play games etc...but so hard to get it stable

Cheers
Sergio

Hi m8,

TBH I was in kind of similar situation beofre at the beggining of OC.

I could do no problem Linx 10 passess but blend would fail in minutes simetimes seconds, sometimes hours and also I had different resoults from day to day for same settings - the reason was simple they were not stable and I need mode volts on most of compononets.

IMHO IBT or Linx are good as finish touch and 12h blend is more reliable - but also as my own example showed even 12h blend stable + 10 linx + Pi32 did not gourntee stability (correct skews does in my case ).

I think you should go back to begginning and work your way up with P95 instead if IBT - I could also run IBT at low voltages but not blend - I am pretty sure your volts are too low for 24/7h.

But I might be wrong of course. Also it would help if you would find point at which you start to be unstable at Auto GTLs. Becouse from ther we can find some nice GTLs for your setup.

Wish you luck and try with all around higher volts and Blend test - in fact forget blend test and do Large FTT.

And about your PSU what volts you got on lines under load?

Cheers

[ci2kla]

Seems more people is interested in tuning GTLs when using Quad core processors.
I have an Q9550 what can pass IBT 10 tests with only 1.2v and I'm wondering if it's GTL / skews related? I've tried GTL0 +50mv but unfortunately the chip seems don't like the juice and hard lock my screen

[mikeyakame]

Seems more people is interested in tuning GTLs when using Quad core processors.
I have an Q9550 what can pass IBT 10 tests with only 1.2v and I'm wondering if it's GTL / skews related? I've tried GTL0 +50mv but unfortunately the chip seems don't like the juice and hard lock my screen

Hard lock usually means FSB wall. Only way I know of to get around this is CPU/NB clock skews and CPU differential amplitude adjustments.

[ci2kla]

Hard lock usually means FSB wall. Only way I know of to get around this is CPU/NB clock skews and CPU differential amplitude adjustments.

Not likely that a Q9550 will hit a wall @ 471...sorry I have to disagree with you
With all GTLs on auto IBT can pass 10 tests with 1.2v, 4003Mhz.
Apart from CPU GTLs, NB GTLs becomes more important as well.
For my example, E8400 need +20mv to get a certain FSB run smooth. But for Q9550 w/ RE, +70mv for vNB GTL is the sweet spot, +60 / +80 setting or add more vtt will cause IBT calculation errors that's my finding so far. Probably now the vtt is higher then vCore (1.206v VS 1.192~1.2v) maybe that explained the problem but I'm not sure...need more time and testing to find out. Will post more soon

[mikeyakame]

Not likely that a Q9550 will hit a wall @ 471...sorry I have to disagree with you
With all GTLs on auto IBT can pass 10 tests with 1.2v, 4003Mhz.
Apart from CPU GTLs, NB GTLs becomes more important as well.
For my example, E8400 need +20mv to get a certain FSB run smooth. But for Q9550 w/ RE, +70mv for vNB GTL is the sweet spot, +60 / +80 setting or add more vtt will cause IBT calculation errors that's my finding so far. Probably now the vtt is higher then vCore (1.206v VS 1.192~1.2v) maybe that explained the problem but I'm not sure...need more time and testing to find out. Will post more soon

You may disagree, but a FSB wall can mean a multitude of things. It's usually a wall that's in place due to clock signals skewing too far apart. If you have the flexibility of bios options to work around then the wall will be higher. All depends on how good you are fine tuning the settings and how fine they can be tuned. RE has a lot of flexibility so if you are stuck at 471 then it's more the fault of the guy playing with the settings than the chip itself

I hit a wall on my Q6600 at 482mhz on RF which isn't a static wall, but without skew adjustment to get around the wall it might as well be a hard wall

[Alien Grey]

Not likely that a Q9550 will hit a wall @ 471...sorry I have to disagree with you
With all GTLs on auto IBT can pass 10 tests with 1.2v, 4003Mhz.
Apart from CPU GTLs, NB GTLs becomes more important as well.
For my example, E8400 need +20mv to get a certain FSB run smooth. But for Q9550 w/ RE, +70mv for vNB GTL is the sweet spot, +60 / +80 setting or add more vtt will cause IBT calculation errors that's my finding so far. Probably now the vtt is higher then vCore (1.206v VS 1.192~1.2v) maybe that explained the problem but I'm not sure...need more time and testing to find out. Will post more soon

And i have to disagree with you.
IBT stable means you have no problem with your CPU stability and that is basically it.
Try to run Prime95 Blend mode and stress you Graphics card and all other components on your system and see if you can do that without problems.
See my sig and you will know what i mean.

[ci2kla]

And i have to disagree with you.
IBT stable means you have no problem with your CPU stability and that is basically it.
Try to run Prime95 Blend mode and stress you Graphics card and all other components on your system and see if you can do that without problems.
See my sig and you will know what i mean.

Are you trying to say I have to stress everything at the same time to make sure the FSB is stable or not? I'm not sure what you mean...
Just done some extensive test. The reason why I choose IBT as the main testing tool is because it is the fastest tool to find out if the system is stable or not (of course not for 7/24). Calculation errors exists not only CPU but also can be other components related...for example...NB GTL vRef

Last Progress so far: 1.2v vCore, 1.32v VTT CPU GTLs all on auto, NB GTLs +70mv, IBT Test = Hard Lock / Reboot
With CPU GTLs slight fine tune, IBT Test 80% correctness, ORTHOS Large FFTs HARD LOCK after 1 hr 47 mins

Will start to try getting 485FSB stable after I'm off and will post up more if any progress made. Cheers

[Alien Grey]

Are you trying to say I have to stress everything at the same time to make sure the FSB is stable or not? I'm not sure what you mean...
Just done some extensive test. The reason why I choose IBT as the main testing tool is because it is the fastest tool to find out if the system is stable or not (of course not for 7/24). Calculation errors exists not only CPU but also can be other components related...for example...NB GTL vRef

Last Progress so far: 1.2v vCore, 1.32v VTT CPU GTLs all on auto, NB GTLs +70mv, IBT Test = Hard Lock / Reboot
With CPU GTLs slight fine tune, IBT Test 80% correctness, ORTHOS Large FFTs HARD LOCK after 1 hr 47 mins

Will start to try getting 485FSB stable after I'm off and will post up more if any progress made. Cheers

Yes i do. IBT is good for your CPU stability and the first step to a stable overclock.

I use 1.22V for VTT as you can see in my sig for FSB 465MHz with CPU GTL 0.63X and NB GTL 0.67X. I can get it IBT stable with 1.16V. Prime95 Large FFT's will fail within minutes with the VTT at 1.16V.
You might need a little bit more voltage on the NB to pass Prime95 Large FFT's than you use for IBT.
To find the right Memory voltage i use MemTest86+ V2.11. If i can pass MemTest86+ V2.11 without errors i have no problems at all with my Memory stability.
The reason that i stress everything on my system is to find the right VTT to keep everything stable.

This may look insane. We are at Xtreme Systems. Why not do extreme stability tests.

Try the latest BIOS for your RE. The latest one for my RF fixed the problem with the VTT. Earlier BIOSes didn't allow me to raise the VTT higher than 1.16V without losing stability in IBT.
The ASUS Tech Support fixed the problem for the RF with BIOS 0701, they released a new BIOS for the RE at the same time. The BIOSes where released a few days after they have tested a system similar like mine to find out why i couldn't raise the VTT without losing stability. I don't know what they did with that BIOS but now i can get it stable with higher VTT.

I have to wait now for my new memory to arrive to see if i can get it stable at higher FSB. The 2 X 2 Giga OCZ Reaper HPC PC2-8500 can't go over 1120MHz with 5-5-5-15 timings.

[CryptiK]

Are you trying to say I have to stress everything at the same time to make sure the FSB is stable or not? I'm not sure what you mean...
Just done some extensive test. The reason why I choose IBT as the main testing tool is because it is the fastest tool to find out if the system is stable or not (of course not for 7/24). Calculation errors exists not only CPU but also can be other components related...for example...NB GTL vRef

Last Progress so far: 1.2v vCore, 1.32v VTT CPU GTLs all on auto, NB GTLs +70mv, IBT Test = Hard Lock / Reboot
With CPU GTLs slight fine tune, IBT Test 80% correctness, ORTHOS Large FFTs HARD LOCK after 1 hr 47 mins

Will start to try getting 485FSB stable after I'm off and will post up more if any progress made. Cheers

Give this a go and see what happens:

GTL 0 = +10mv
GTL 1 = -35mv
GTL 2 = +10mv
GTL 3 = -35mv

Also to test CPU use Small FFT's & IBT, large FFT's more tests the ram & NB. However if your cpu is quite unstable, it can still cause large FFT's to fail.

[andressergio]

Hi m8,

TBH I was in kind of similar situation beofre at the beggining of OC.

I could do no problem Linx 10 passess but blend would fail in minutes simetimes seconds, sometimes hours and also I had different resoults from day to day for same settings - the reason was simple they were not stable and I need mode volts on most of compononets.

IMHO IBT or Linx are good as finish touch and 12h blend is more reliable - but also as my own example showed even 12h blend stable + 10 linx + Pi32 did not gourntee stability (correct skews does in my case ).

I think you should go back to begginning and work your way up with P95 instead if IBT - I could also run IBT at low voltages but not blend - I am pretty sure your volts are too low for 24/7h.

But I might be wrong of course. Also it would help if you would find point at which you start to be unstable at Auto GTLs. Becouse from ther we can find some nice GTLs for your setup.

Wish you luck and try with all around higher volts and Blend test - in fact forget blend test and do Large FTT.

And about your PSU what volts you got on lines under load?

Cheers

Thank you Seban, on 8,5multi this situation is different i am much more stable and with more patterns than on 9 multi

will keep on testing

Cheers
Sergio