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Discussion Starter #1
I'm getting a TRUE heatsink/fan to use with my C2D E8400 CPU and P5B Deluxe Motherboard. However, I've been reading and it looks like my motherboard has a "strap" located at 401 FSB.

From what I've gathered, everything under 400 FSB starts at 1066 but than once you hit 401 FSB it drops to 1333 and loosens it's internal timings.

Example:
400 FSB = 400 * 4 = 1600 FSB (quad-pumped)
401 FSB = 1333 + ((401 - 401) * 4) = 1333 FSB
402 FSB = 1333 + ((402 - 401) * 4) = 1337 FSB

I'm not sure if my formula is correct but I know the quad-pumped FSB drops down to 1333 once you hit 401 FSB.

Besides that, I've also been told that a 1600 FSB requires very, very, very high northbridge voltages and is almost impossible to get stable, so it's better to go for 401 FSB and use the more relaxed timings, etc.

Is this true?

I'm hoping to around 3.8 GHz with my E8400 which is 422 FSB.

(Sorry for mixing up the FSB and quad-pumped FSB terms. Are there better terms for them?)
 

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I think you may confusing strap and fsb frequency. The strap is mainly just the subtimmings of the northbridge and they change on these boards as you go thru them. THe P965 series mobos usually changed out of the 1066 strap once above 400fsb.

This is why the abit quadgt and dfi P965s were two of the fasted mobos clock for clock becuase they would stay in the 1066 strap no matter the fsb.

The holes are just areas where the mobo wont want to boot. Its basically a change over in straps and it causes for some reason a dead spot. With the p5b-d you should have no issue above that up to around 500 and maybe a little higher if you got a good mobo. The p5b-d does usually have a fsb hole in the 400 area so just stear clear of it.
 

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Discussion Starter #3
Thanks for the reply.

I might be getting myself a little confused but I've read that Asus changed the strap ranges so my motherboard will go into the 1333 strap at 401 FSB which means my northbridge subtimings will be slower like you said...

Do these straps affect RAM timings? I'm running "budget" G.SKILL RAM (4x 2GB) and always use a divider that puts the RAM around 800 MHz or a little slower to be safe...
 

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Quote:

Originally Posted by sofakng View Post
Thanks for the reply.

I might be getting myself a little confused but I've read that Asus changed the strap ranges so my motherboard will go into the 1333 strap at 401 FSB which means my northbridge subtimings will be slower like you said...

Do these straps affect RAM timings? I'm running "budget" G.SKILL RAM (4x 2GB) and always use a divider that puts the RAM around 800 MHz or a little slower to be safe...
It could effect the ram subtimings but I am not totally sure. If I remember correctly it did not change the ram timings. Im pretty sure that those were dependent on the ram speed that you have it at like 800,1066 or whatever else you get it too.
 
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