Bus speed problem

[Tibus]

Hi, am new at overclocking, my spec is :

 

CPU : Intel® Core™2 Duo Processor E4500 / cooling : Zalman CNPS-9500A

RAM : 4x DDR II 1GB, PC6400, 800 MHz

Motherboard :P9657AA-8KS2H

Power Supply : Corsair CMPSU-550VX 550W

 

This is the max that i have reached :

the RAM index was at 667 Mhz and all voltage default

 

I want to overclock the cpu higher but i have problem when i increase the Bus speed over 250 my pc will crash

 

I tried with :

minimum cpu multi 6X

minimum RAM index 533 Mhz

and when i increase Bus speed over 250 pc crash...

other trie was to increase Vcore +0,1 ; Dram +0,1 and same...

[sack_patrol]

I'm not very knowledgeable when it comes to Intel but I think that you'll need to raise the CPU vcore a bit more. A 0,1 increase isn't nearly enough for a bus speed increase on any cpu. Also you might want to try the bus speed increase with stock ram settings to see if it isn't bottlenecking, in which case I think you migh also need to increase the Dram with more than 0,1.

[supermep]

Did you disable "turbo boost" before attempting to overclock?

[Tibus]

Did you disable "turbo boost" before attempting to overclock?

 

i don't have this option, anyway all overclock is on manual

[RJR]

You have your memory strap @ 3:5, change it to 1:1 until you get your final OC and then you can adjust if needed.

 

Should take care of any Ram problems for you.

[Tibus]

You have your memory strap @ 3:5, change it to 1:1 until you get your final OC and then you can adjust if needed.

 

Should take care of any Ram problems for you.

 

i don't have option in BIOS for FSB : RAM ratio, for RAM i can only change the index Mhz 533 667 or 800

[RJR]

i don't have option in BIOS for FSB : RAM ratio, for RAM i can only change the index Mhz 533 667 or 800

There should be someway to adjust the memory strap, have you tried the 533 and 800 and opened cpu-z to see the results? You should be able to tell in the Bios also, when you change the value and the ram speed changes to twice the FSB it will be running at 1:1

 

This should take the ram out of the equation and allow you to OC without having to deal with ram and cpu overclocking at the same time.

[Tibus]

There should be someway to adjust the memory strap, have you tried the 533 and 800 and opened cpu-z to see the results? You should be able to tell in the Bios also, when you change the value and the ram speed changes to twice the FSB it will be running at 1:1

 

This should take the ram out of the equation and allow you to OC without having to deal with ram and cpu overclocking at the same time.

 

i tried with all index RAM : with 533 and 667 Mhz it crash when i increase the BUS speed over 260 , at this index at BUS 260 RAM will be 7xx and 8xx

with 800 Mhz i tried only with BUS at ~220 Mhz because the RAM was at ~1000 MHz and i belived was to high already....

[RJR]

Well, from what I can gather your board should be capable of obtaining a FSB of 340-350, in that range MAX.

 

You have to determine what is holding it back, whether vcore, vdimm, NB voltage, cpu termination voltage, ram speed, etc. or a combination of a few settings. You need to try and eliminate as many as possible without blowing up your computer. I would download the Data Sheet from Intel "HERE" to find out the Absolute max voltages and work backwards from there (I normally go the other way but it's easier to go from max). You could start out by setting the vcore to 1.5v, memory to 2.2v, nb (mch) to 1.5v, etc. and see how far you can push the FSB. Just make sure you monitor your core temps and keep it below the high 70's (77-78c). And, of course, once you determine your max OC, start lowering your voltages, you don't want to run at max all the time.

 

Without being at your computer to figure it out and having never owned a Foxconn 965 MB, that's about the best I can do for you.

[Tibus]

thx for reply, i had another trie :

 

CPU multiplier 6x ( minimum )

RAM index 533 Mhz ( minimum )

 

Vcore +0.15 -> total 1.5 V

Dram +0.3 ( at +0.4 -> total 2.2 V cpu don't start )

Mch +0.2

Cpu Term V +0.120

 

cpu still not start with 265 Mhz BUS speed...i tried in so many ways so i am at the conclusion that don't let me go over 260 Mhz, don't know why

 

i overclocked the memory just for testing and at 800 Mhz index with 260 Mhz cpu started ---> RAM was at 1040 Mhz, so i think is not the RAM fault

 

the single thing that i don't modified was the RAM timing, always was on auto, i don't know if this with overclock can be the crash motive...