problem with CORSAIR memory on intel D865PERLX motherboard

[ipokrov]

Hello,

I have a problem (a lot of problems, this is one of them :)) I have a D865PERLX motherboard with Celeron 340 2.93Ghz 533FSB CPU and with CORSAIR 1GB (2x512MB) DDR3200 memory letency 2.5. I bought and tried to install CORSAIR 2GB (2x1GB) DDR3200 memory latency 3 and the computer would boot to the log in screen and than a would get a blue screen. I tried everything and I could only get to work by installing all 4 memory modules, but it comes up with and error at bios level "SPD is missing.. memory be used a lowest speed 333", but it works. what is the problem? :(:

Anyone?

Thanks ilya

[RJLeong65]

The problem with the Intel-brand motherboards is that they adhere strictly to Intel's chipset specs. You cannot operate PC3200 memory at DDR400 with a QDR533 FSB CPU. That's because Intel's chipsets officially support asynchronous memory operation only up to HCLK +/- PCI. You see, PC3200 memory is actually clocked at 200MHz - but your Celeron's FSB has an actual clock speed of only 133MHz. That would result in a 67MHz differential between the memory clock speed and the CPU's FSB clock speed, which is outside Intel's official specs. (The specs say that you can use only PC2100 or PC2700 DDR memory with a 533MHz FSB CPU.)

 

In addition, you're mixing different memory modules in the same system. I don't recommend mixing different models of modules in the same system, since they all have different brands of chips and different voltage requirements.

 

The D865PERL series of motherboards, however, do allow for a manual override of the memory clock speed. In this case, the best that you can do with PC3200 DDR memory and a 533MHz FSB CPU is to manually override the automatic memory speed selection and set the memory clock speed to either 266MHz or 333MHz (Intel's way, although those settings are actually 133MHz and 166MHz, respectively). After manually setting the memory clock speed to DDR266 or DDR333, you may also want to manually change the CAS latency setting to CAS 2.5 if the memory is rated at CAS 3 @ DDR400.