XMS3 timing help needed

khare

khare

khare

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Hi guys. I've got 4gb (2x2gb) of Corsair XMS3 1600 and I'm wondering if my timings are right?

Untitled-9.jpg


As you can see under the memory tab timings are 8-8-8-20-27 1T (by the way I don't know what the hell any of them mean :D) but under the SPD tab when I select my ram slot it shows 9-9-9-24-41 2T. From what I've read the timings are 9-9-9-24 2T as in the SPD tab (where did the 41 go?). Which ones are the current memory timings and are they correct or should they be changed at all? If so could someone please give me a very quick run down on how to do so in the bios?

Thanks
 
Your memory is running at ~1333MHz (2 x 662), 8 8 8 20 with a Command rate of 1.

To run the memory at its specified spec you'll need to manually set it up as follows (or enable the XMP in the BIOS):

  • 1600MHz Frequency
  • 9 9 9 24 timings
  • 2T Command rate
  • sub 1.58V if possible if you're running a clocked SB (this will default to 1.65V if you enable the XMP which isn't a problem)
 
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Don't have XMP (that's Intel right? I've got AMD), so manual setup is the only way. I've got an OC system by the way, I thought FSB was connected to ram? Because it's stable as it is at the moment but if I up the ram to get to 800mhz ram frequency it's unstable.

This is what I've got in my bios.

IMG_20111013_191832.jpg


Then a long list of what to me look like random scattered letters lol

IMG_20111013_191445.jpg

IMG_20111013_191504.jpg

IMG_20111013_191513.jpg
 
khare said:
Don't have XMP (that's Intel right? I've got AMD), so manual setup is the only way. I've got an OC system by the way, I thought FSB was connected to ram? Because it's stable as it is at the moment but if I up the ram to get to 800mhz ram frequency it's unstable.
Click to expand...

I'm not familiar with amd - the last AMD set up i had was T-Bird and you had to use the pencil trick to unlock the CPU.

If your system buckles at higher frequencies then i would stick with the timings and command rate that it's set at already as they're tighter (faster) than the default timings at 1600MHz.

At present your memory is running at (on auto):


  • 1324MHz Frequency
  • 8 8 8 20 timings (faster)
  • 1T Command rate (faster)
  • 1.65V - not a problem

If things are stable and you're happy with the frequency/clock settings you could leave things as they are.
 
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Thanks guys. Right went into bios (before either of you posted) and set the timings to this (Chris now I read your post I'll go back into bios and change tRC to 41 as it's 27 at the moment.

IMG_20111013_200235.jpg


As you can see I can't change the command rate, so it's stuck at 1 I guess.
 
You've adjusted all the setting correctly but you do realise you're now running the memory slower than it was when it was on auto?

If you weren't having stability issues with your previous settings but still want to enter the values manaully you would be better off inputing your old values:

TCL = 8
tRCD = 8
tRP = 8
tRAS = 20
CR =1
and the memclock value back to 662 (~1333)

e.g. your original memory tab:

Untitled-9.jpg
 
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More importantly you are running your memory in single channel mode, which means you have them in the wrong slots. You need to sort that out before anything else. ;)

Also your NB frequency is underclocked, you might want to knock the multi up one.
 
HeX said:
More importantly you are running your memory in single channel mode, which means you have them in the wrong slots. You need to sort that out before anything else. ;)
Click to expand...

Good spot missed that.

Basically khare you're not squeezing all the available speed out of your memory. Dual channel mode (*especially* dual channel mode) and tighter timings all help.
 
That might explain 800 odd points I'm missing in 3dmark that I was going to post about hahaha. Wait a minute so what slots should my ram be in? I've got it in the first black and first blue ones, dimm_a1 and dimm a_2, should it be dimm 1_1 and dimm b_1? Yeah I raised cpu/nb multiplier and it's 1986 now, might knock it up one knotch more though.
 
just had a read of the mobo's manual and says channel A is A_1 and A_2 and channel B is B_1 and B_2. Is that what you meant HeX?
 
Ah right ok. Yes there's 2 blue and 2 black. They used to be in both blues but I read in this forum somewhere that it should be on a_1 and a_2 so I changed them over! Silly me, will change them right away!

Guys...Amazing help, much appreciated!
 
I have the same memory and tried running mine at 800Mhz with a CAS of 8.

Unstable........the XMS3 only seems to like 9-9-9-24.
 
Mine is running stable with the lower timings, but it's running 1333mhz rather than 1600mhz. Would like the full 1600mhz but the fsb:ram ratio can't adjust to my liking.
 
ChrisGTL said:
I have the same memory and tried running mine at 800Mhz with a CAS of 8.

Unstable........the XMS3 only seems to like 9-9-9-24.
Click to expand...

True when running XMS3 at 1600MHz - 9 9 9 24 with a command rate of 2T (the recommneded settings) - is usually all it will tolerate.

However, khare is running his memory at 1333MHz which is why it's tolerating the tighter timings.
 
Tighter timings = lower number = better performance right?

If so, do you reckon I could get away with maybe lowering the timings 1 more knotch to see how low I can get?
 
khare said:
Tighter timings = lower number = better performance right?
Click to expand...

Yes, but the reality is that you wont notice any discernable difference in day to day usage between such minor changes - unlike single and dual channel mode.

The only reason i mentioned you change your settings back is that there seemed little sense in slackening timings that had proved stable.

khare said:
If so, do you reckon I could get away with maybe lowering the timings 1 more knotch to see how low I can get?
Click to expand...

I would leave well alone as your clock is stable and you haven't tested the dual channel mode with your present timings for stability (it should be fine but you still need to monitor stability over the next couple of weeeks.)
 
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Understood. Will run memtest and also prime95 on in plage large FFT's to see if overall system is stable. Just ran 3dmark 11 and where as last night I was baffled as to why I was getting physics results of 2690 rather than 3461 which is what I got just now. All down to me being a plonker!
 
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