1.8v or 2.0v PC6400 DDR2 800MHz

50bmg

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Is 1.8v or 2.0v. Do i need to stick with 1.8v? I am looking for PC6400 DDR2 800MHz. Will 2.0v work in a 1.8v mobo? I have the opportunity to get some real cheap.
 

50bmg

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An Asus P5** that is about 2 years old. I would assume 2v in an 1.8v mobo would be better than 1.8v in a 2v mobo. You know what assume means.
 

homerdog

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Actually there's no such thing as a "2V mobo." All motherboards must comply with the JEDEC standard for memory voltage, which is 1.8V. Whether or not higher voltages are supported is up to each individual motherboard manufacturer.

Just about any motherboard will run RAM at 2.0V if configured properly in the BIOS; the question is whether or not the board will recognize the RAM as requiring 2.0V and adjust itself accordingly so it will boot for the first time. If the board does not do this then you won't be able to use 2.0V RAM unless you first use 1.8V RAM and set the board to 2.0V in the BIOS.

While we're on the subject, there's no such thing as "official" 2.0V RAM. Since there is no JEDEC spec above 1.8V, all RAM running higher voltages is simply over-volted 1.8V RAM.
 

50bmg

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I was just making a point with the 2v mobo. For example, putting a mobile cpu in a desktop mobo. The higher voltage mobo would fry the lower voltage cpu. I know someone that did that back when AMDs had socket A's for mobile and desktop.

I dont think my old current mobo has ram voltage adjustments. I will be buying a new mobo soon anyway. I will just save this ram, regardless if it works in my current mobo. Its a good price.

It sounds like it wont hurt the 2v ram if i try it in the 1.8v mobo? At worst it won't boot. If it doesn't boot i will put my 2G of 1.8v DDR2 667mhz back in my current mobo.
 

homerdog

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No, there is no such thing as a 2V mobo. The mobo will run the memory at whatever voltage the memory is specified to run at. The mobo will not fry the memory unless you manually set the voltage too high.
If your mobo doesn't have voltage adjustments then it probably won't support 2.0V RAM.
Correct.
 

Iain1974

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This makes me curious.

I notice that Crucial Ballistix Tracer requires 2.2v. If the standard is for 1.8v and a few little LED lights don't take much power then how many motherboards will support this memory or would it just run underclocked?
 
Most New MB would have no problem. Although the Ram is listed as 2.2 Volts, It will (should) boot with looser timings. This allows you to go into bios, adjust voltage and timings.

Some boards (ie older versions of gigabyte 965 Rev 1) had problems. In many cases you could boot using a single stick, although some still had problems and required the 1.8/1.9 V ram to get into bios and set the voltage.
 

homerdog

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Good to hear. RAM voltages are one of the most confusing (in my opinion) areas of PC building. The JEDEC specifications could be a lot better, or at least have some profiles for high performance memory.