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Memory Latency Compatability

I have ASUS Laptop Series K52jc with 4G memory and running at 2.4Ghz. I have attempted to upgrade the memory to 8g. I bought 2 x 4g sticks of "4GB PC3L 12800 CL11 204 pin SODIMM"
and added them, no success. I then tried 2 x "4G of 4GB 10600 CL9 204 pin SODIMM" and they failed. on each account reverting back to the origonal 2G sticks, the computer rebooted.
I read through some of your literature on memory and followed up by downloading and running CPI_Z.
From the CPU_Z screen and under SPD I see that the current memory is PC3_10700(667)mhz and under that in column JEDC#4, freq is 666Mhz and CASLatency is 9.0, RAS to CAS 9, and RAS Precharge is 9.
Being confused some what, the question is? Why would the second set of chips fail even with a Latency of 9 and does the latency follow the frequency hense the PC3L set having a higher latency of CL11. Does the CPU / Bios adjust to latency of the supporting chips.
Thanks.
5 answers Last reply Best Answer
More about memory latency compatability
  1. Latency cannot really be adjusted. Assuming that this is a stock computer it is always best to go with the same RAM type. Have you tried both your Alpha and Beta SO-DIMM modulea or a mix of both?
  2. You could try a bios update to see if that makes a difference.
  3. Best answer
    Vic hit it, check for a BIOS update, the BIOS needs to be able to automatically adjust CL (timings to get the DRAM to play nice, and most laptops have a locked BIOS so you can't manually make adjustments (also laptop makers seldon put a lot of time into the BIOS, they just as soon have you buy upgrades direct from them (at often inflated prices)...if no joy return what you bought and look for a stick with identical timings and freq
  4. Thanks all, have upgraded chipset but not BIOS, Will try.
  5. gaininfo said:
    Thanks all, have upgraded chipset but not BIOS, Will try.

    Let us know if that did the trick.
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