A wise idea to upgrade memory?

pgi947

pgi947

pgi947

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Hi all.

Recently moved over to X79 and started to overclock with my 3820 and 16GB (4x4GB) 1600mhz vengeance memory on a UD7.

From what I have gathered once I start playing with the BCLK I have to start adjusting the memory to suit.

Firstly I have a couple of questions about my current memory, I don't know a great deal about memory but I figure I will have to learn at some point. The default XMP timings are 9-9-9-24-2T, the profile stated tRFC is 48. When I switch to XMP on the motherboard the timings switch to 9-9-11-24-1T with a tRFC of 138 - do these sound drastically wrong? Also CPUZ states the quad speed is 800mhz, surely this should be 400mhz in quad channel?

Also while playing with the BCLK I ended up at 1666mhz, gave it a little nudge on voltage to 1.55v from 1.5v and windows insta-crashes even with no CPU OC.

SO am I doing something wrong or missed a setting to help keep things stable?

Starting to think life would be easier with some of the samsung green memory as I shouldn't need much of a voltage nudge to apply light clocks to the memory.

Thanks in advance :D

Edit: Some info today would be brilliant as the samsung green is down to £90 for 16GB today only!
 
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Also CPUZ states the quad speed is 800mhz, surely this should be 400mhz in quad channel?
Click to expand...

CPU-Z simply states your RAM speed is 800MHz.

This is doubled to 1600MHz as it's Double Data Rate.

It has nothing to do with the number of channels.
 
Ahh all this time I thought the speed shown was representative of the number of channels. That's one thing explained then :)
 
Ok so I've been having a play in the bios this morning as well as some reading up on memory timings! A little more educated than I was yesterday but could still do with some pointers.

Managed to set 4.625ghz with a 100.00 base, 1.25x strap, 37x MP, set memory voltage to 1.6v, manual timings of 10-9-10-25-1T running at 1666mhz from the multiplier, the tRFC clock is now set 144, with tRFC lower = faster, higher = stability?

I did coincidently manage to set (by accident I might add) the memory to 2000mhz with timings of 12-10-12-35-1T @ 1.6v - are these timings too slack, or do I have at least some hope of not buying some new memory?

Edit: Note I may be able to get the higher speed timings tighter, I haven't tried at all yet, I left something on auto and it manually set to those timings for 2000mhz, speed is not important but keeping decent timings while clocking the CPU is for me.
 
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could try 10-10-10-30-1t timings,but you may have to push dram voltage too high idk unless you test
 
What would you deem as too high? I'd be happy enough pushing 1.65v, any higher than that I may as well look at picking up some of the samsung green stuff :)

Edit: also, those timings, is that for 1666 or 2000?
 
1.63v is as high as id go,i have run 1.65v for short periods,trouble is x79 doesnt have high read/write ram speeds anyway,idk if youd benefit from samsung or push the vengeance,do you have aida64 or maxmem? could post some read/write figures
 
Cheers:

Maxxmem & Aida64 benches:

aida64.jpg


MaxxMEM2_f1536.jpg


This is for current settings/timings for 1666mhz.
 
see how far you can push things now,what dram voltage was that with? stock 1.55v?

this is the samsung 8gb @2133mhz but x79 is a little slower than z68/77 anyway

dbmypg.jpg


in the timings the last timing,the highest one will reduce latency if you can lower it

with 16gb i needed 1.6250v dram voltage,with 8gb i needed 1.55v dram,depends on cpu/motherboard,stock vccio of 1.05v also
 
That was at 1.6v, iirc I tried 1.55v yesterday but with automatic timings (so no idea what they were set at as the system crashed before I could check).

So would a good place to start be to tighten down the timings @ 1666mhz (current) or leave the timings and try raise the speed?

Seems a good place to start on the memory, at least then I will know where I stand on heavier overclocks.
 
yeah try and see how far you can tighten timings at 1666mhz,then later you can see how a higher freq with looser timings vs lower freq and tighter timings compares regarding read/write/copy figures ect

try and find a middle ground,from 1600mhz to 2133mhz im only 5-6mb per second more,so not much in it tbh
 
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Now at 9-9-9-24-1T at 1666mhz 1.6v

Seems I may not need new memory after all :)

new_aida64.jpg


I could try dropping the memory voltage a little. Happy enough with 1666mhz as thats full speed on a 1.25x strap :D
 
could try upping ram freq with slightly looser timings? see if you get more read/write? or leave em as they are and try lowering dram,looks ok though,the latency has dropped from 50 odd to 48ns
 
Ok just trying out 2000mhz (its the next logical speed on a 16x memory multiplier) with 11-11-11-32-2T @1.6v still, latency as gone back up, but read has increased:

2000_aida.jpg


Would a good idea with 2000mhz be to aim for something along the lines of 11-10-11-30?
 
Haha I spoke too soon!

The above settings for 2000mhz instantly killed my machine as soon as I started to prime.

I'll stick to tweaking 1666mhz just now :)

Thanks AGAIN for your help wazza, you're a credit to the forums :)
 
haha ok no probs,maybe 8pack can help you tweak them further

EDIT: one or two clicks more vccio might help you,idk if its needed with bclk straps
 
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