I am wondering what type of memory to get for my Lenovo g560e laptop with a T4500 intel Dualcore CPU at 800 MHz FSB. I know that the DDR3 shipped were 1333, 2+1 gb. I have heard that not only speed is important but also wether it is synchronous or asynchronous to the cpu. What option is then better for me a 1066 or 1333 memory upgrade.
The 1066 MHz model is a CL7 module, CL9 for 1333.
Since it lists both DDR3 PC3-8500, DDR3 PC3-10600 either will work - BUT most Notebooks have a VERY limited BIOS so more than likely you cannot increase the DRAM Frequency above it's minimum. To verify either go into you BIOS or use CPU-z -> http://www.cpuid.com/softwares/cpu-z.html note the Memory tab and IF it list DRAM Frequency = 533 then 533 x 2 = DDR3 1066 is your limit; your DDR3 1333 is ignored and down-clocked. Next look at the SPD tab and COMPARE the 533 CAS timings to you MEMORY timings -- IF there different then you BIOS is using safe DDR3 1066 CAS Timings and there will be ZERO benefit from Low CAS and/or Higher Frequency.
In short, if my assumptions are correct then get the CHEAPEST compatible RAM per the Density you need. Ideally, is Best of both DIMM slots are populated with IDENTICAL RAM.
Let me know.
If the tab memory in cpu-z said frequency is 399 MHz, does it mean that even the shipped 1333 mzh modules were downclocked to some much lower speeds, even lower than 1066?
IF per 'Compare 'Running'' - the DRAM Frequency = 399 MHz X 2 == 800; then yep you're running them at DDR3 800 MHz.
In your BIOS is there any mention to DRAM Frequency or Memory Speed or Memory Multiplier -- where you can CHANGE the values?
nope, it all is unchangeable.
I will test i further tomorrow and write back. From what I see, it does run max 800 MHz, maybe a cpu limitation.
Just to describe my whole situation:
The system was shipped witx 1+2 gb 1333 sticks, it all works fine. I decided to upgrade to 8 GB because I like to play with virtual machines and I bought this memory http://www.patriotmemory.com/products/detailp.jsp?prodl...
Only later I realized that they were "only" 1066. As a friend of mine is considering an upgrade himself too, I have given him my 2x4 modules for weekend testing. If he decided to get a set for himself, he could get me the 1333 modules and he could keep the 1066.
As the 1333´s are CL 9 - the description you gave to me , if I understood it well means, that they would run on 800 MHz but on CL9 rendering them even slower than CL7 1066 modules?