I7 920 and memory timings

[0Artur0]

One month ago I had no clue about overclocking and stuff... today I'm a proud owner of i7 920 and I know some basics about overclocking. So I OCd my proc to 3.8GHz and is running stable with max temps at 74°C. I made these changes in the BIOS, everything else is on default settings:

Multi: x20
BLCK: 190
Vcore: 1.3
QPI/Vtt volts: 1.35
DRAM: 1.65
QPI Link: x36
Uncore Freq: x17
System MemMult - 8x
HT off, turbo off

The only thing I still have no clue about even though I read tons of forum posts and tutorials and stuff I'm still clueless. I'm talking about memory timings... My memory: MUSHKIN 3x2GB HP3-12800 DDR3 3x2GB 1600MHz. My motherboard: GA-EX58-UD4. Timings in BIOS are on auto and they are (I think) 10-11-11-28 (see first picture). As far as I know those are pretty bad. Now.. I can manualy insert numbers for timings but I suspect I can't just enter 9-9-9-24 or can I?

Pictures:
Picture 1
Picture 2
Picture 3

 

[BTRY B 529th FA BN]

Did you read this?

 

[0Artur0]

I did it now. This article didn't answer my question.
I still don't get the theory behind timings.
I' be very happy if somebody would say "Yes, just enter 9-9-9-28 and you're good to go". Or, "No, don't do that.. you have to know this and that to know the right numbers" and of course what this and that is.

 

[BTRY B 529th FA BN]

There is a tool out there called Nehalem Calculator 1.3 that will better help you understand how fast your memory is working. If you are under the rated speed, you can most certainly plug in the rated timings from the manufacturer.

 

[BTRY B 529th FA BN]

O and welcome to the Anandtech forums

 

[0Artur0]

Thank's for that info! I just got the app... nice, but not much help. The frequncy my memory is working at is 1520. I'm asking about timings... "Picture 1" shows clocks.. 10-11-11-28... the memory should be running at 9-9-9-24. Can I just change from auto (10-11...) to manual and enter 9-9-9-28. If so, why in the world is memory on auto not running at those timings? See.. timings are, for me, one of those things you just don't understand.

 

[TheInfernal]

Try these timings and test the RAM stability using Memtest.

 

[BTRY B 529th FA BN]

Ok, so we got the memory speed which is 1520, now I'm not sure but I think you can manually adjust the timings to the advertised speeds seeing that 1520 is under the 1600Mhz speed. If you are having problems with the timings at that speed like boot failures, try memtest86 v2.11 - you'll need to burn it to a disk and boot straight into it from bios. You'll need to change the bios order to USB CDRom or CDRom, first. Memtest86 v2.11 will check for any errors being returned by you RAM kit.

 

[0Artur0]

I don't know if I'm going to have problems, since I don't know what can potencialy be problematic and why those timings are not chosen automatic...so I'm asking a noob question Ok, I'll try than.

One more thing.. if I set BCLK to 200 (no other changes) than I get 4GHz and memory at 1600MHz (on the calculator). Can I do this, considering voltages I posted above.

BTW, I have D0.

 

[BTRY B 529th FA BN]

You can just leave the Bclock at 200 by 20 for 4Ghz. The 200 is one of the things that plays with the memory timings. You can also set the CPU multi to 19 and get 3.8Ghz while still maintaining 1600Mhz with the memory because the 200 BClock is being multiplied by the memory multiplier of 8 (which I think you are using) that gives you the 1600Mhz. You can change the memory multi to 7 or 6 but always keep the uncore >=2x the Memory Multiplier.

 

[0Artur0]

Thank you!!!
Using this tool I found one more thing.. My QPI Multi is 36.. this calc only has 18, 20, 24. I set it manualy to 36 but it gives me warning "Instability may occur when QPI clock is greater than 4000MHz". Mine is 7200. Is this ok?

 

[BTRY B 529th FA BN]

Originally posted by: 0Artur0
Thank you!!!
Using this tool I found one more thing.. My QPI Multi is 36.. this calc only has 18, 20, 24. I set it manualy to 36 but it gives me warning "Instability may occur when QPI clock is greater than 4000MHz". Mine is 7200. Is this ok?

You'll have to ask someone more qualified for that. I'm not sure... Do a Google search and see what comes up about it.

 

[ScorcherDarkly]

Short answer, yes, you just type in the timings you want. If your memory is running at or below the rated frequency, then plugging in the rated timings should work out fine. If you want to go lower, you can try it but there's no guarantee your system will remain stable. Usually to get lower timings you also need to lower the speed.

 

[aigomorla]

what voltage is your ram set at.

To answer your question... its a big maybe.

if your running the ram downvolted 1.5-1.6v, then id say a big fat no.
If your running the ram @ stock voltage, or higher, a number like 1.65v then most definitely.

If your running 1.65v on your ram, please make sure your cpu voltage is higher then 1.15v

 

[Shmee]

aigomorla, when you say cpu voltage, you mean QPI VTT and not Vcore, correct? As I understand it, memory Voltage should be within .5 V of uncore/QPI VTT. Vcore should be higher than 1.15 anyways if he is ocing, and so should the QPI VTT I believe. 200 BCLK usually needs a bit of a boost from my findings.

 

[0Artur0]

As you can see in post nr. 1 I'm running DRAM: 1.65 and QPI/Vtt volts: 1.35 so I should be fine. I'll try it. Thank you!

 

[0Artur0]

I did it and it works.

 

[0Artur0]

I'm now at stock timings 9-9-9-24.
Just a question for somebody who knows stuff... can I do better?