What is the limiting factor when trying to run a High HT(FSB)?

[ty1er]

What is the limiting factor when trying to run a High HT(FSB)?

No matter how low i set the Memory divider, HTT ratio, and CPU Mulit my PC will not boot with the FSB higher than 250mhz.

Is this just the limititations of my Asus A8V mobo, or does it have anything to do with with CPU it self?

Bassically im asking, no matter how many times i change my cpu my FSB wont run any higher then it is now.... right?

 

[Peter]

For starters it might well be that the clock signal itself degrades in quality far enough as it travels from the clock PLL chip to the processor.

 

[ChineseDemocracyGNR]

Have you tried the latest official BIOS?

What happens at 251MHz, no POST? And is 250MHz stable?

 

[ty1er]

Originally posted by: ChineseDemocracyGNR
Have you tried the latest official BIOS?

What happens at 251MHz, no POST? And is 250MHz stable?

yes im running the lastest final BIOS.

I was just testing in 5mhz FSB increments on how high my mobo would go.
from the stock 200 to 245 all seemed to work good. but when i tried 250 or above the PC would not boot. The monitor would not even turn on. I would then have to hit and hold the power botton for a Hard Reboot then the post screen would display the msg "failed to boot, OC failed. press F1 to go into BIOS, or F2 to load defaults" (or something like that). Then i would have to back down the FSB.

My whole reason for starting this thread was to find out that
just because my BIOS gives the option to run the HT/FSB from 200, 201, 202 all the way up to 300mhz. Does Not Mean that the mobo will run at the high 300mhz setting. right?

 

[ahurtt]

Originally posted by: ty1er

My whole reason for starting this thread was to find out that
just because my BIOS gives the option to run the HT/FSB from 200, 201, 202 all the way up to 300mhz. Does Not Mean that the mobo will run at the high 300mhz setting. right?

Absolutely right. What you have just done is taken the first step in finding your systems max stable overclock. You should check out this thread:
http://forums.anandtech.com/messageview.aspx?catid=28&threadid=1497607

You've probably just run up against the max capability for your rig for HTT/FSB speed.

 

[GuitarDaddy]

CPU should not affect your max HTT. The limiting factors on HTT IMO are

Mobo - chipset voltage, chipset temps, etc...
Power supply - amount of amps supplied to the mobo, fluctuations in amps/volts