Overclocking Xeon 5450(LGA775)

[ibex333]

Please help me understand what is going on. I been using Hynix DDR2 667Mhz RAM, (5-5-5-15) which allowed me to get to 3.8Ghz on the CPU. At this setting the RAM runs at 890MHz.

This seems to be the red line here, because if I go any higher, either the system wont boot or it boots and there's BSODs, errors, etc.

I am pretty sure that RAM is the limiting factor here, because the CPU temps are fine, and plenty of people got their X5450's to 4.0GHz and beyond. Therefore I bought some more expensive RAM on ebay.

It's OCZ Platinum Edition 1066MHz (5-5-5-18). I popped it in and thought I would easily get to 4.0GHz now, but guess what... I cant even break 3.0GHz !!! Anything higher, and the system wont boot! To get the CPU to even the same 3.8GHz, the RAM overclocks way above 1066 MHz...


Why is this, when the Hynix RAM could do it at 890MHz which was much less? What am I doing wrong?

 

[ibex333]

I think I got it. It has to do with SPD settings... Running at 2.0 it will be 800 something, and 2.4 will be higher, and so on.


Lowering SPD to 2.0 I am able to run at 3.8 again, but still cant go any higher. What gives? It cannot be a CPU limitation. It's capable of 4.0 GHz.... The RAM and mobo are compatible... WTF?

 

[SPBHM]

you could try lowering the CPU multiplier to test if the problem is the FSB clock or just the CPU clock,
I don't know the specifics of your board but you might have to look at other settings like fsb voltage, mch votage and so on to achieve higher FSBs

 

[kirbyrj]

You don't know if the CPU is limiting you or not. All you noted is that other people's CPU's hit 4Ghz. Yours just might not work at 4Ghz.

 

[Hi-Fi Man]

You need to lower the RAM multiplier (if you can). The RAM can only go so fast so try to keep it as close to stock as possible.