# Safe volts on DDR2?



## JC316 (Jan 31, 2007)

I need to know what the max safe voltage is on them, my AC freezer is right over the top of it. I am currently runnin 2.1V, and my board max is 2.2V. Can I run 2.2V safely?


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## niko084 (Jan 31, 2007)

I honestly can't say for your ram... But I wouldn't doubt it could take the extra .1 as long as your board has good voltage control.


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## JC316 (Jan 31, 2007)

niko084 said:


> I honestly can't say for your ram... But I wouldn't doubt it could take the extra .1 as long as your board has good voltage control.



It should take it, but I want to confirm just to be safe.


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## niko084 (Jan 31, 2007)

JC316 said:


> It should take it, but I want to confirm just to be safe.



Makes enough sense, blowing stuff up in never fun.


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## JC316 (Jan 31, 2007)

niko084 said:


> Makes enough sense, blowing stuff up in never fun.



Espically when you just got the stuff  .


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## infrared (Jan 31, 2007)

DDR2 ram can generally handle 2.1v quite happily, as long as the dimms aren't getting too warm, i'd give 2.2v a shot. I used to have a kingston 512mb 533mhz dimm (value select) and it could hit over 800mhz on 2.4v  They seem to handle the voltage ok imo, but since it's value it's always a gamble.


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## niko084 (Jan 31, 2007)

infrared said:


> DDR2 ram can generally handle 2.1v quite happily, as long as the dimms aren't getting too warm, i'd give 2.2v a shot. I used to have a kingston 512mb 533mhz dimm (value select) and it could hit over 800mhz on 2.4v  They seem to handle the voltage ok imo, but since it's value it's always a gamble.



They can really take that much, like normally... Hmm now I wonder what I can do with my XMS2 ram if I ran it up to 2.1-2.2 volts... Or if my controller is stopping me from running 800mhz on my ram...

Ohh well at 4-4-4-12 I can run about my ram at about 720 at 1.8 volts


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## infrared (Jan 31, 2007)

You can go up to 2.4v without worrying niko  some nice ram you got there! But if you can run nice frequencies/timings with low voltage there's no need!

I can run 800mhz 4-4-4-10 on my Crucial 667mhz dimms at 1.8v, so i very rarely need to use anything higher than 2.0v for normal use, and for benching i jump to 2.4v 1000mhz 4-4-4-10 1:1


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## pt (Jan 31, 2007)

infrared said:


> You can go up to 2.4v without worrying niko  some nice ram you got there! But if you can run nice frequencies/timings with low voltage there's no need!
> 
> I can run 800mhz 4-4-4-10 on my Crucial 667mhz dimms at 1.8v, so i very rarely need to use anything higher than 2.0v for normal use, and for benching i jump to 2.4v 1000mhz 4-4-4-10 1:1



i use 2.3 for 1120mhz 5-5-5-14 for everyday use


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## niko084 (Jan 31, 2007)

infrared said:


> You can go up to 2.4v without worrying niko  some nice ram you got there! But if you can run nice frequencies/timings with low voltage there's no need!
> 
> I can run 800mhz 4-4-4-10 on my Crucial 667mhz dimms at 1.8v, so i very rarely need to use anything higher than 2.0v for normal use, and for benching i jump to 2.4v 1000mhz 4-4-4-10 1:1



Wow good to hear I honestly wasn't too sure of the ram as far as how good or average it was.  I don't think I will be pushing it too far yet. Having a few issues with my machine running hot. Honestly its probably not even hot to a dangerous point, but I have this thing about feeling a heatsink and feeling heat... And seeing my proc up around 50c isn't cool to me.....


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## niko084 (Jan 31, 2007)

Heh just figured on a quick reboot I would see what I can do without any work at all I have my ram running at 800 3:5 4-4-4-12 2.1 volts....

Wondering though how in the world would I get 1:1?


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## niko084 (Jan 31, 2007)

Eh I just did some reading... From the looks of it 1:1 timings on ram is almost a bad idea... Because you have to raise your timings most the time, and in turn that actually hurts your gaming performance.... Hmmm ya don't think I will worry about that too much, but instead I think I might try to push for 4-4-4-10 or better.


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## JC316 (Jan 31, 2007)

Ok thanks, with your confirmation and Ashen's as well, I will go ahead and bump it to 2.2V. I am not too worried about the heat, my AC freezer is sucking air right over the top of the chip.


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## pt (Jan 31, 2007)

niko084 said:


> Eh I just did some reading... From the looks of it 1:1 timings on ram is almost a bad idea... Because you have to raise your timings most the time, and in turn that actually hurts your gaming performance.... Hmmm ya don't think I will worry about that too much, but instead I think I might try to push for 4-4-4-10 or better.



from what i read on intel you have more performance with more mhz instead of amd we're you have more performance with low timmings


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## JC316 (Jan 31, 2007)

Well, I was in for a shocking suprize. My motherboad claims that the DDR voltage jumper will take it to 2.2 volts, yet in the BIOS it listed it as 2.48 volts , so I switched it back to 2.1V.


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## Zebbo (Jan 31, 2007)

Before asking for safe voltage, be sure to measure the real voltage with DMM, you never know how much boards over/undervolts. There's also a very simple voltage modification you can do for Biostar boards which has the 2.2V VDIMM jumper and it requires no soldering on board: http://www.xtremesystems.org/forums/showpost.php?p=1631098&postcount=29

Back to topic, for 24/7 system I would go with 2.25V or 2.3V definately at max (with active cooling, direct airflow to modules).


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## JC316 (Jan 31, 2007)

Zebbo said:


> Before asking for safe voltage, be sure to measure the real voltage with DMM, you never know how much boards over/undervolts. There's also a very simple voltage modification you can do for Biostar boards which has the 2.2V VDIMM jumper and it requires no soldering on board: http://www.xtremesystems.org/forums/showpost.php?p=1631098&postcount=29
> 
> Back to topic, for 24/7 system I would go with 2.25V or 2.3V definately at max (with active cooling, direct airflow to modules).



Thats what I was using and it decided to crank it to 2.48V, not 2.2.


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## Zebbo (Jan 31, 2007)

JC316 said:


> Thats what I was using and it decided to crank it to 2.48V, not 2.2.



2.48V measured with digital multimeter? Shame on me for doing this (I should be comparing cherries to cherries), but Biostar TForce590 gave ~2.35V when 2.2V jumper was set 2-3 position. BIOS reported voltages can be way off.


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## JC316 (Jan 31, 2007)

Zebbo said:


> 2.48V measured with digital multimeter? Shame on me for doing this (I should be comparing cherries to cherries), but Biostar TForce590 gave ~2.35V when 2.2V jumper was set 2-3 position. BIOS reported voltages can be way off.



No, I didn't check it with the multimeter. I ASSumed that the BIOS was correct, it probably is 2.2V.


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## bcracer220 (Jan 31, 2007)

2.2volts is safe for most, i wouldnt go any higher if  i were u though


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## infrared (Feb 1, 2007)

niko084 said:


> Eh I just did some reading... From the looks of it 1:1 timings on ram is almost a bad idea... Because you have to raise your timings most the time, and in turn that actually hurts your gaming performance.... Hmmm ya don't think I will worry about that too much, but instead I think I might try to push for 4-4-4-10 or better.



Not neccessarily. Usually you have to use a fairly high fsb though. 

Example: to run generic 533mhz ddr2 dimms at 1:1, you must have a 266mhz fsb. 667mhz ram would require a 333mhz fsb to run at 1:1 and 800mhz ram would require 400mhz fsb and so on.

You only need to loosen the timings on the memory if it is becoming unstable while using higher frequencies, and if you can't/aren't willing to raise the voltage anymore. This has to do with frequency, not the divider you use.

1:1 means the ram is "in sync" with the fsb, which gives the best performance because the ram can be accessed with every clock cycle, 3:4 (example) means the memory isn't syncronised.

I hope this helped


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## niko084 (Feb 1, 2007)

pt said:


> from what i read on intel you have more performance with more mhz instead of amd we're you have more performance with low timmings



That all depends on what you are doing.. If you need lots of bandwidth from your ram *large applications that don't read/write small chunks of ram extremely frequently* you need a more mhz, if you are playing games or doing other things the read/write very often in smaller blocks you don't need all the bandwidth and need faster timings for more performance.

I just tested it running cs:source because it was already installed. At 3-3-3-8 and 540mhz I got 94fps with my settings. When I brought it up to 800mhz and dropped my timings to 4-4-4-12 at raised voltage to 2.1 to hold it I dropped to 91fps. Tested each 4 times to make sure.


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## niko084 (Feb 1, 2007)

infrared said:


> Not neccessarily. Usually you have to use a fairly high fsb though.
> 
> Example: to run generic 533mhz ddr2 dimms at 1:1, you must have a 266mhz fsb. 667mhz ram would require a 333mhz fsb to run at 1:1 and 800mhz ram would require 400mhz fsb and so on.
> 
> ...



Ya thats helping clear some stuff up with some of the other stuff I'm looking at... I don't know if I can get my fsb to 400mhz that would REALLY be pushing it give me 5.6ghz if I could though... But my board says it only supports 667 anyways and at 333, that would give me 4.6... Man ohh man.... I wish I could unlock my multiplier


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## Ketxxx (Feb 1, 2007)

depends on the ic used on your sticks. general rule is dont go above 2.2v if u dont know the ic used. D9 fatbodys are good to 2.4v, above that they will fry pretty fast.


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## niko084 (Feb 1, 2007)

Well I just found out I can't even get it to run at 300mhz fsb.... I tried boosting the voltage and dropped my ram to 600 for 1:1, I either get no video signal and once I get that windows blows up on boot...

I'm still fairly new to heavy over clocking. Is there anything I am missing here? I boosted my voltage to keep it up, ram should be fine because its actually running slower than it normally would.

And curious what kinda stuff if any should I be setting for my FSB Termination voltage, PCI Frequency? Or should that all just stay auto anyways? I honestly don't even know what thats used for.. Besides the obvious.


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## pt (Feb 1, 2007)

Ketxxx said:


> depends on the ic used on your sticks. general rule is dont go above 2.2v if u dont know the ic used. D9 fatbodys are good to 2.4v, above that they will fry pretty fast.



do you know if the adata ddr2 800 extreme edition are D9 
it likes voltage


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