Does Voltage matter?

[fishquail]

I'm still confused. If my motherboard says it takes RAM that is 1.8V then can i buy ram that says it is 1.8V - 1.9V and it will work?

Motherbord is Gigabyte GA-X38-DQ6. I'm terrified i'm choosing the wrong ram. Out of this list which should i get? Here are my requirements; Need 4GB kit. 2x2GB modules only. DDR2 800 - anything better is too expensive.

1)
G.SKILL 4GB(2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model F2-6400CL5D-4GBPQ - Retail
http://www.newegg.com/product/product.asp?item=N82E16820231122

2)
mushkin 4GB(2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory
http://www.newegg.com/product/product.asp?item=N82E16820146731

3) CORSAIR 4GB(2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory
http://www.newegg.com/product/product.asp?item=N82E16820145184

 

[MrCommunistGen]

The mushkin has the best specs. 1.8V and faster timings than the others. Lower voltage is a good thing. Means things run cooler and that the chips are capable of running fast without an increase in voltage. I have no idea what the quality of the actual RAM chips (the ICs?)... thats not my area of expertise. Are you looking to overclock?

-mcg

 

[RetiredChief]

No problem on Voltage.

Typical range for DDR2 is 1.8 -> 2.2. The higer voltage is normally used for lower timings.

example my DDR2 memory is 2.2 for a timming of 4-4-4-12, however; when I first installed it the MB (Gigabyte P695-DQ6) was defaulted to 1.8 V. The memory worked but with higher timing - 5-5-5-18.

The DDR2 voltage on your board is adjustable, and you may need to bump it up to get stable operation. Remember to run a memory testing program to verify stability, ie Memtest86. I would recommend that you run this from bootable CD PRIOR to installing Operating system, or downloading any bios update.

Memory problems can really mess up an installation, or a bios update!

 

[fishquail]

What? I don't want to mess around here. I need it to be stable right away. I'm not going for overclocking anything. Im just looking for the best performance and best stablitiy i can get.
That darn motherboard memory recomendation list dosnt have anything in 2GB Dimms that are for sale anymore. The list seems out of date. Only thing i found they stop selling or its overseas. So im stuck trying to figure out RAM that will work with my board just by specs alone.

 

[fishquail]

or what if i went with this ram? The Timmings are low. Voltage dosnt match the 1.8V but not sure that matters? Should I buy this?

Brand G.SKILL
Model F2-6400CL4D-4GBPK
Type 240-Pin DDR2 SDRAM
Tech Spec
Capacity 4GB(2 x 2GB)
Speed DDR2 800 (PC2 6400)
Cas Latency 4
Timing 4-4-4-12
Voltage 2.0V - 2.1V

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231148

OR IS THIS BETTER: Its DDR 1066 2x2GB - however the Voltage is 2. Price is twice as expensive. Not sure its worth it.

Brand GeIL
Model GX24GB8500ESPDC
Type 240-Pin DDR2 SDRAM
Tech Spec
Capacity 4GB(2 x 2GB)
Speed : DDR2 1066 (PC2 8500)
Cas Latency: 5
Timing: 5-5-5-15
Voltage : 1.9V - 2.5V

http://www.newegg.com/Product/Product.aspx?Item=N82E16820144110

 

[Zorg]

If your really terrified then make sure it's on this list. motherboard_memory_ga-x38-ds5.pdf

 

[fishquail]

I did look at that List; Thats my BIG PROBLEM. They are way out of date. There are no 2GB DIMMS on there that are still sold anywhere. So I am forced to try to figure it out myself. - which is scary.

 

[MrCommunistGen]

Ram spec'ed for higher voltage probably wont be stable at low (stock) voltage. You can always increase the voltage on the motherboard but a lower voltage requirement should be viewed as a good thing. As I said before the mushkin has the fastest timings of the original 3 you mentioned, requires only a very small voltage increase (or might even work fine at the stock 1.8v), and isn't really expensive like the Geil. If you're not overclocking you don't need faster RAM, and on the Core 2 architecture the timings don't make a huge difference. You should be able to pick any of those and be fine as long as you adjust the memory voltage to where its supposed to be.

-mcg

 

[Zorg]

I did look at that List; Thats my BIG PROBLEM. They are way out of date. There are no 2GB DIMMS on there that are still sold anywhere. So I am forced to try to figure it out myself. - which is scary.

I didn't look at the list closely. That's pretty weak, I hope they update the QVL. As far as being concerned with voltages, don't be. The board will easily power any of those sticks. The problem, as I remember, was with people using sticks that only operated at 2.2+ voltages. The older boards e.g., 965/975 would not boot with RAM that required excessive voltages to run. The work around was to boot with a stick of 1.8V RAM and change the voltage in the BIOS and then swap to the high performance RAM. The RAM and mobo manufacturers realized that they were pissing a lot of people off, so they made higher performance RAM that would operate at 1.8-1.9 volts with relaxed timings and mobos with better auto voltage control that would raise the voltage if it was needed. Between the two they pretty much eliminated the problem. The reason that I said look at the QVL is that some ram is a little more fickle with certain mobos than others. Get the RAM with the best timings at the lowest voltage. A lot of the RAM these days is designed to run at 2.2V and the higher voltage it isn't a problem. The reason for the 1.8V in the specs is because that is the JEDEC standard, unless they have changed it.