Phenom II 965 & 1600 RAM

pwnttothemax

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So I just ordered my new PC from cyberpower. They were offering a free upgrade from 1333 MHz RAM to 1600, so naturally I took it. I read somewhere that the phenom II 965 doesn't support 1600 though.

Does that mean that my RAM just won't work in the system, or will it be automatically clocked down to 1333? Let's just say that I don't OC my computer either. I don't want that to be involved in this thread, please. I just want to know if the RAM is compatible.
 
D

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If the motherboard supports 1600 then yes, it will most likely downclock it to 1333 in bios you would have to change the ratio to 1.4, but the cpu doesn really effect this a athlon 2 640 supports 1600 ram:)
 
1333mhz ram with a Cl of 7 is faster than 1600mhz ram with a Cl9.
Playing with CAS Latency gives very little real-world benefit. Playing with frequency (speed) however, gives noticeable real-world benefits. The lower-latency RAM might respond slightly quicker to a transfer request, but the higher speed RAM will definitely finish the transfer faster.
 

sofyanator

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They are selling you 1600mhz ram so it should operate as 1600mhz ram. If it doesnt work you can make them rma the board or ram and they will probaly give you a upgrade to 1600mhz board for incovenience. Also most asus boards have a cool button called "MemOk"(the idea is if your mem doesnt work you press it and tada... it does!
 
that's where people make the mistake. Lets look at my example

DDR3 1333mhz CL 7
1.5x7=10.5ns

DDR3 1600 CL9
1.25x9=11.5ns

You were saying?
Re-read my post. As I said before, the CL7 memory will respond quicker to the request. However, the actual transfer will complete quicker on the higher-bandwidth memory.

Remember, we're talking about nanoseconds here. That's one billionth of one second.

I'm perfectly happy with my 12GB of 1600 CL9 RAM in my Sandy Bridge system. :p
 
Yes, and you tell the IMC what speed the RAM is in the BIOS, like always.

The low-CL memory responds to the request quicker and starts the transfer quicker. The higher-clocked memory responds a few ticks later, and starts the transfer later. Once the transfer starts, the higher-clocked memory quickly catches up and passes the low-CL memory. It finishes the transfer quicker and is ready for another command quicker, even if the theoretical maximum bandwidth is never reached. The actual bandwidth of 1600 will be higher than the actual bandwidth of 1333.

Remember ... Sandy Bridge has an IMC too, and that bit-tech article said 1333 CL7 was worse on all tests than 1600 CL9 for it.
 


Yes *











* assuming the RAMs have been qualified for that motherboard by the OEM


 
It doesn't matter that the data doesn't "fill" 6.4Gbps. Any amount of data will travel faster down a pipe running at 1600MHz effective clock speed than if the same pipe was running at 1333MHz effective clock speed.

The only advantage the low-CL low-clocked memory has is that it will respond to the transfer command quicker. If the chunk of data being transferred is small enough, it could finish faster and be ready faster. But once that threshold is reached, the high-CL high-clocked memory will finish the transfer faster and be ready faster despite responding to the transfer command slower.
 

joefriday

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They both play a role. This has been studied in great detail here on Toms:
http://www.tomshardware.com/reviews/phenom-ii-ddr3,2319.html
 

kakanutto

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Rápido y al pie...1600Mhz no son necesarios, salvo pretendas subir la velocidad de CPU y quieras una velocidad acorde en las ram para evitar errores de calculos (eso cuando tenemos un procesador a velocidades superiores a los 4.0Ghz).