If I'm overclocking my FSB, and CPU, I am NOT supposed to have the memory speeds over 800Mhz no matter what?
Nvidia based chipset like your's allow to set the FSB and the memory frequency independently , while Intel chipset is limited to 1:1 ratio or higher .
In your case u can set the memory frequency totally independently from the FSB .
In CPU-Z it says the DRAM frequency is running at 400Mhz, and the FSB:DRAM is 1:2 is that right?
In this case your memory frequency is 400x2 = 800 Mhz and your cpu system bus (FSB) is @ 200 mhz , since your E5200 come with 12.5 multiplier so your cpu run @ its default 200x12.5 = 2500 MHz .
Also, should I change the command rate from 2T to 1T?
1t command give always better performance , but In Intel based system the 1T command rate will severally limit your FSB and memory frequency , so it is better to leave it @ 2T .
I just know the website said 4-4-4-12, but my previous BIOS settings were higher than that, like 5-5-5-18. I at least changed that much so far, and the system runs fine.
Those are the memory latencies , lower value = higher performance, according to corsair data sheet : http://www.corsair.com/_datasheets/TWIN2X2048-6400C4.pdf
your memory can do 800 Mhz with 4-4-4-12 (2.1V), so if possible u can set them manually and increase your memory voltage to 2.1v (note the default DDR2 voltage is only 1.8v and if your motherboard do not allow memory voltage increase then your memory can't run@ its default frequency or my cause some stability problem with 4-4-4-12 timing) ,
SO in your case u can set them manually (4-4-4-12)and check your memory stability with memory test , if its stable then you are lucky , if not then you will be limited to the 5-5-5-18 regime due to the lack of bios voltage settings.
Your motherboard do not allow cpu voltage tweak and your cpu overclock will be severely limited (expect from 2.8- to 3.2 Ghz in the best case). But there one solution : called hard mod voltage modding for the cpu and memory .
This require some soldering skills and in this case u will lose your motherboard warranty .
Maybe this motherboard is more advanced than I think, although I highly doubt it.
You are right , your motherboard is very limited . The motherboard is the key of successful and stable overclock , so ask for advice next time before making purchase .
Usually your cpu with stock cooler can do : 3.2 up to 3.6ghz , with after market cooler : 3.4 - 4 ghz or even more with some luck .
Moreover even with voltage modification your motherboard will not do over 400 Mhz FSB (usually 300-350 range) (even your cpu has a FSB wall @ 300-350 Mhz -- i already tested several most cap out @ 340 MHz , only few get as high as 380-390 Mhz), but this is pretty enough for 4 Ghz but require a lot of work (volt modding , cooling and checking ) .
My suggestion get a rid of it , there are many cheap motherboard which will overclock your cpu correctly , Ebay is your freind
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