Question about DDR3

[brandonvi]

Hello i was just told recently that DDR3 has to be fixed in size for all chips for example you cant have 2x2GB and 2x4GB togeather from what i have been told you can only do 4x2GB or 4x4GB so i was wondering if anyone can tell me this is right? i know this is not the way it was with old DDR ram since in my last computer i had 2x512MB and 1x1GB chip and they worked fine togeather

also if anyone has any idea why they did something like that i mean it just seems so stupid to do ya there is a small chance when people upgrade they would just go and buy all 4GB chips but more then likly people would buy 2GB chips and end up spending less even if they had the money for 2x4GB

 

[cburke82]

Hello i was just told recently that DDR3 has to be fixed in size for all chips for example you cant have 2x2GB and 2x4GB togeather from what i have been told you can only do 4x2GB or 4x4GB so i was wondering if anyone can tell me this is right? i know this is not the way it was with old DDR ram since in my last computer i had 2x512MB and 1x1GB chip and they worked fine togeather

also if anyone has any idea why they did something like that i mean it just seems so stupid to do ya there is a small chance when people upgrade they would just go and buy all 4GB chips but more then likly people would buy 2GB chips and end up spending less even if they had the money for 2x4GB

If i am understanding your question then that would be wrong. I currently have one 2GB stick and one 4GB stick and they are both different cas timings as well lol. Now that is not the best setup performance wise and im sure there are some issues that might happen but its working fine for me. Hope it helps

 

[brandonvi]

ya thats more or less what i was talking about anyone else useing combs of differnt size rams so i cant conferm its not just AMD that works this way

 

[jb6684]

You should always install 2 sticks that match in size and timings for optimum performance. This is so you RAM will run in Dual Channel mode. And, so that the system will set a CAS & other timings that will work both sticks. And finally, Intel & AMD CPU chips will over clock the best with ONLY two sticks.....

But you can use 4 sticks. The second 2 sticks should match each other. The do NOT have to match size or even the timings of the 1st 2 sticks. This is true since system will run at the timing for the SLOWER pair of sticks. Size doesn't matter at all...

An time you use an odd number of sticks, you'll run Only Single channel which slows your computer down quite a bit.....

For proof, look up the manual for your motherboard. Then read up on the allowed RAM combinations....

 

[brandonvi]

Best answer selected by brandonvi.

 

[brandonvi]

ya that is more or less what i thought Jb6684 but they where telling me i was wrong thanks for the confermation

 

[jb6684]

Just noticed your signature, every current CPU supports Dual channel RAM, EXCEPT the i7-900 series from Intel. That's Triple channel. SO, same rules apply:

You should always install 3 sticks that match in size and timings for optimum performance. This is so you RAM will run in Triple Channel mode. And, so that the system will set a CAS & other timings that will work both sticks. And finally, these Intel i7-900 series CPU chips will over clock the best with ONLY three sticks.....

But you can use 6 sticks. The second 3 sticks should match each other. The do NOT have to match size or even the timings of the 1st 3 sticks. This is true since system will run at the timing for the SLOWER triplet of sticks. Size doesn't matter at all...

An time you use an Even number of sticks, you'll run Only Dual channel which slows your computer down quite a bit.....