OC Help - FSB / Memory interaction

[RustyTinMan]

Hi... I am in the process of building a new system which will be :

Asus P5B Deluxe
E6400
2X1GB OCZ DDR2 PC2-6400 Platinum Rev 2 http://www.ocztechnology.com/products/memory/ocz_ddr2_pc2_6400_platinum_revision_2
TT Bigwater 735

I haven't tried overclocking before & have been reading as much as possible so I can have a fair idea of what I'm doing before all my parts arrive.

I have read the Core 2 Duo OC Guide and understand most of it.
The part that is confusing me is:
Part.2 Memory adjustments

ASUS: Set ‘DRAM Frequency’ to DDR2-533 @266Mhz FSB (1FSB:1RAM operation)
As you increase the FSB, the RAM will follow in the pattern of 1:1 shown in BIOS.

1. Set ‘DRAM Timing’ to manual or disable SPD (use SPD for P5W DH)
2. In BIOS you will see 4 separate timing digits, change them to the ones specified on your RAM

e.g. 4-4-4-12
CAS# Latency (tCL)
RAS# to CAS# Delay (tRCD)
RAS# Precharge (tRP)
RAS# Precharge Delay or Active to Precharge (tRAS)

When 1FSB:1RAM is overclocked above the rated frequency of your RAM use the following values
Timing: 5-5-5-15
vDIMM: 2.2V

e.g. DDR2-667 4-4-4-12 1.9V operating at ~400Mhz will need to be set to 5-5-5-15 2.2V

So 1FSB:1RAM means that the RAM is operating at the same frequency as the FSB ? For the E6400 this would end up high 300s to low 400s from the results I have seen?
Where does the 400MHz stated above for DDR2-667 come from? Isn't DDR2-667 800MHz RAM ?

For the OCZ RAM I'm getting should I use 4-4-4-15 and 2.2V?

Thanks in advance.

 

[yas]

When the ram operates at a 1 to 1 ratio it means twice that of the FSB. For example a FSB speed of 400mhz gives a ram speed of 2 x 400mhz= 800mhz. Different RAM have different speeds like 667 or 800. If you plan to OC then getting 667 will limit your FSB while 800 will allow you to hit higher FSBs.

 

[rwaritsdario]

For the OCZ RAM I'm getting should I use 4-4-4-15 and 2.2V?

You can go up to 2.325v with EVP.
Run those timings only at 400Mhz or less, slack them for higher frecuencies.