4 DIMM vs 2 DIMM for Stability and Overclocking

[cbuchach]

I upgraded to 4 DIMMs on my Asus P5W DH several months ago and have never been happy with the overclocking performance and stability of the board since then. With 2 DIMMs the board overclocked beautifully with good stability. With the 4 DIMM config, I of course have been limited with my maximum FSB speed to around ~380-385, but this has been a bit flaky. The board will pass Memtest86 for several runs and then immediately after a restart will crash on some of the tests. The board also on occasion will fail to boot entirely at the high FSB settings. I have to remove all the memory then replace a few of the sticks and somehow magically it works again (I leave the system on 24x7 so it isn't a huge issue, but a little disconcerting). I have been running stabley recently at 4:3 FSB:Memory with high FSB settings and complete stability without any of the aforementioned issues, but I am losing performace, especially on video encoding and things with the lower memory settings.

My question is, with the inexpensive 2GB DIMMS out there, do you guys think that moving to a 2x2GB configuration will help these issues?

 

[BlueAcolyte]

Yes.

 

[nullpointerus]

Slightly OT:

Have you tried increasing DIMM voltage w/ 4 DIMMs?

 

[Atheus]

The received wisdom says 2 modules is best.

 

[myocardia]

Originally posted by: nullpointerus
Have you tried increasing DIMM voltage w/ 4 DIMMs?

And more importantly, have you increased your northbridge voltage? Running 4 sticks of RAM is ~twice as hard on the northbridge chipset as running two sticks of RAM.

 

[Cutthroat]

I am successfully running 4x1GB at 1:1 ratio at 475MHZ FSB, VDIMM @ 2.3v, NB voltage @ 1.7v. It's very dependent on the quality of your motherboard and RAM.

 

[cbuchach]

I have tried altering voltages, bringing my RAM up to 2.3 and upping the voltage on the MCH an termination voltages but with no luck. It is quite a strange issue where it will pass Memtest on a cetain set of settings then go back and fail when I test at a later time--so it is hard to consistently reproduce or test.

But, it sounds like going back to 2 DIMMs should solve these issues--thanks guys.

 

[nerp]

Lots of variables come into play. My opterons both were able to OC a little higher on my EpoX board with just 2x1GB sticks as opposed to 4. On an nforce4 board, lowering commandrate was another reality you had to face when populating all four banks. I didn't notice any stability issues in general, but yes, the OC was not as easy to achieve and I had to settle for a few less mhz.

That experience is what compelled me to get 2x2gb sticks for my new build. I originally was going to just get 2GB of ram to start but I wanted to run in dual channel and I figured that i'd be better off in the long run with larger sticks. I'm glad I did it.

 

[Idontcare]

Originally posted by: Cutthroat
I am successfully running 4x1GB at 1:1 ratio at 475MHZ FSB, VDIMM @ 2.3v, NB voltage @ 1.7v. It's very dependent on the quality of your motherboard and RAM.

Holy Jebus Krist! :Q

I ran my Mushking redline DDR2-1000 at Vdimm of 2.2V with active cooling for 13 months and I killed off all four sticks. One was completely dead, the other 3 wouldn't pass memtest+ at DDR2-800 without errors.

Got to love Mushkin though, they replaced all 4 sticks even after I told them how abusive I was on them and that I didn't really want a replacement if it wasn't in their policy to do so. They still replaced them, and gave me some helpful advice on how to not burn them up again. (keep teh uber voltage under 2.2V if you want >12 months lifetime)

 

[Markfw]

Originally posted by: Idontcare

Originally posted by: Cutthroat
I am successfully running 4x1GB at 1:1 ratio at 475MHZ FSB, VDIMM @ 2.3v, NB voltage @ 1.7v. It's very dependent on the quality of your motherboard and RAM.

Holy Jebus Krist! :Q

I ran my Mushking redline DDR2-1000 at Vdimm of 2.2V with active cooling for 13 months and I killed off all four sticks. One was completely dead, the other 3 wouldn't pass memtest+ at DDR2-800 without errors.

Got to love Mushkin though, they replaced all 4 sticks even after I told them how abusive I was on them and that I didn't really want a replacement if it wasn't in their policy to do so. They still replaced them, and gave me some helpful advice on how to not burn them up again. (keep teh uber voltage under 2.2V if you want >12 months lifetime)

The factory voltage on many of my PC-8000 sticks is 2.3-2.4 vdimm. I don't run ANY of my memory over factory specs. However, I have had 4 pairs go bad.....

 

[Idontcare]

Originally posted by: Markfw900

Originally posted by: Idontcare

Originally posted by: Cutthroat
I am successfully running 4x1GB at 1:1 ratio at 475MHZ FSB, VDIMM @ 2.3v, NB voltage @ 1.7v. It's very dependent on the quality of your motherboard and RAM.

Holy Jebus Krist! :Q

I ran my Mushkin redline DDR2-1000 at Vdimm of 2.2V with active cooling for 13 months and I killed off all four sticks. One was completely dead, the other 3 wouldn't pass memtest+ at DDR2-800 without errors.

Got to love Mushkin though, they replaced all 4 sticks even after I told them how abusive I was on them and that I didn't really want a replacement if it wasn't in their policy to do so. They still replaced them, and gave me some helpful advice on how to not burn them up again. (keep teh uber voltage under 2.2V if you want >12 months lifetime)

The factory voltage on many of my PC-8000 sticks is 2.3-2.4 vdimm. I don't run ANY of my memory over factory specs. However, I have had 4 pairs go bad.....

My Mushkin specs were 2.2-2.3V too, the problem (as I learned too late) is some motherboards and chipsets are notorious for "over-volting" the ram to give the user the impression of teh uber stability with their manufacturer?s board.

i680 and Striker Extremes apparently fall into this category, as when I first inquired with my plight the Mushkin guys first question was "did you happen to be using an i680 board?"...which I was.

Setting a BIOS V-dimm at the upper spec for the ram is kinda pressing your luck from what I gather because the motherboard guys don't have to deal with your RMA to the ram makers, but I'm not hear to preach to anyone so I'll leave it at that.