This Strapping, what is that?

[Infa]

Hi, i wonder more or less in detail what this strap is and does.

i know its about how the cpu works at stock fsb or something like that!
but, can u change it on every C2D ? couse i have a LOW fsb wall on my 6600.

if someone could explain the whole strap thing, it would be sweet :)

regards :)

[adamsleath]

well as far as i know; ram latencies are changed on 680i/650i at 425fsb...the effect being that you get crappier read write scores at 425 fsb vs <425...i've seen the effect but i dont understand it.

[elsupremo]

Everytime I see a big post about overclocking, I see this and that about "strap" constantly thrown about, but I've yet to see a good explanation of it. :D

[Omastar]

Strap defines a set of chipset latencies. The lower the strap (1066, 800), the tighter the latencies (just like with RAM timings) and thus, more performance, to put it very simply. However, when you lower the strap you usually won't be able to hit as high an FSB as you were before. That is, on the 975X chipset you may be able to do 470FSB on the 1333 strap, but on 1066, you may only be able to hit 435. Just as an example, don't quote me on those numbers, of course.

So higher strap = higher latencies, worse performance, higher FSB potential.
Lower strap = lower latencies, better performance, lower FSB potential.

[loc.o]

On your P5B booting under or at 400 FSB = 1066 strap and above 401 from bios youll be on 1333.

[HoriWanderFuLL]

Yes all affects diff cpus n such in diff ways...My commando let my E6600 boot right up to 445 fsb with 9 multi.

my Quad core it wont let me boot up at 400 fsb !!! BUT it handles 401 fsb no worries.....

and 460 fsb with 8x multi is also verry easy with the quad...Yet with the E6600 8x460 was a no go ....i thought it was my memory ..obviously wasnt.

Ps.. also at 400 fsb my benchamrks are way faster than 401 fsb ther next strap..it took me to at least 430 fsb to cach up to the 400 fsb benchmarks.

so like some already posted obviously the 400 fsb strap is tighter timings just like ram has when u reach its peak........


hope this helps probably not but anyway..

Cheers Hori

[Infa]

Well, thanks its making a bit more sense :)

thats why i have like someone said, at 400fsb and mem at 1200 my bench was 9900 in everest, and 48ns :)

and when i set 8x475 for example, i get 8600...and 60ns.

and my cpu doesnt go further than 480, ive tried that with low multi...maybe it does? should i try to go higher? and see if it skips and boots at 500? :)

thanks!

[ahpaul82]

This is what i get in my ASUS P5N-E SLI :

400x8 :
Avg Memory Read : 10011MB/s
Memory Latency : 53.6ns

425x8 :
Avg Memory Read : 9021MB/s
Memory Latency : 70.1ns

http://img103.imageshack.us/img103/7328/comparekp8.th.jpg (http://img103.imageshack.us/my.php?image=comparekp8.jpg)

[Infa]

Well i tried just now, 8x480 .. it went 9600 in READ and 8600 in WRITE
but now in 9x400 it says 9900 in READ and 7290 in WRITE. .. this is WEIRD :)

[Zucker2k]

Hi, i wonder more or less in detail what this strap is and does.

i know its about how the cpu works at stock fsb or something like that!
but, can u change it on every C2D ? couse i have a LOW fsb wall on my 6600.

if someone could explain the whole strap thing, it would be sweet :)

regards :)

Here's another analogy:

Ist Gear = 533 strap (133)
2nd Gear = 800 strap (200)
3rd Gear = 1066 strap (266)
4th Gear = 1333 strap (333) (Native strap for bearlake therefore no performance loss; i975x, P965 non-native relaxed strap to enable higher frequency ie. trade performance clock per clock for max frequency).
5th Gear = 1200 (400) - Future intel chipset - Native strap, no performace loss.

The lower the gear, the higher the power produced (acceleration, clock per clock), but the top speed suffers - you cannot accelerate all the way to 300 miles an hour in 1st gear. However, when you change to 4th gear it's like accelerating from standstill in 4th gear all the way to the top speed of the car. Acceleration will be relatively slow till you get to the higher rpms.

On the 975x chipset the strap is set @:

533 (133) - 160~180mhz
800 (200) - 300~320mhz
1066 (266) - 400~500
1333 (333) - 400~525

These numbers are rough estimates and depend on hardware as well as skills of the overclocker. As we all know, many variables impact how far one can push a chipset or component.

Hope I got it right. Regards.

[Infa]

Hmm i see that you got both 1066 and 1333 strap on the same FSB..
how do i then know wich strap that is used?

cheers!