NB voltage questions

[razor]

hey guys,

 

so, I'm trying to find out a few things on what effect adjusting my NB voltage would have. firstly I guess, is there a single place on the Net where I can go read and figure this out by myself? also, my NB voltage options go up in increments of .08v - is this normal, or is this a large increment? lastly, I guess, does adjusting the NB voltage have more effect on the CPU/FSB or RAM? I checked out the Northbridge Wikipedia page, and it seems as though the NB is kind of the communications hub between the CPU, RAM, and PCI-E.

 

I'm not sure if this is related to NB voltage, but my PC wont reboot if I bump the RAM voltage up to 2.7v, even though the product page at NewEgg claims I should be fine anywhere between 2.6v-2.8v. I also checked out the product page on OCZ's website, and only 2.6v and 2.8v are mentioned - does this mean that 2.7v isnt supported? if I'm missing anything important, please fill me in.

 

EDIT: forgot to post some possibly important #'s...

- FSB: 248mhz

- RAM speed: DDR496

- vCore: 1.375v

- vDIMM: 2.6v

- NB/SB voltage regulator: 1.52v

[Waco]

Each chipset reacts differently to more voltage. Some overclock like mad with stock voltage and falter the instant you add more, some overclock horribly until you pump up their voltage. It's really just a case of trial and error for most boards, though I wouldn't boost it too far if the first few bumps don't result in any added stability.

[Hyper Threaded]

You'll need to keep check on NB temps once you increase the voltage. Possibly look into improved cooling for it, as well.

[hardnrg]

I found the chipset* voltage worked best at 1.6v on my DFI NF4 boards... 1.5v was a lot less stable, and 1.7v was slightly less stable

 

I suggest booting up with a Memtest86 bootdisk, or a dos bootdisk/flashdrive with Memtest86+ on it, and running test 5 (moderately hard) or test 8 (very hard) looping (when Memtest86/86+ is running, press: C, 1, 3, 5, enter, 0.... or C, 1, 3, 8, enter, 0) and make sure there are no errors, then reboot and increase the OC slightly, run Memtest86/86+ again on test 5 or 8 and hopefully you can get it so that you get a few errors like 20 or something... then reboot and change the chipset voltage, run the same tests and see if the number of errors increase or decrease significantly... this way you can home in on the least unstable (or stable) voltage, and then just use that voltage for your stable OCs... you can use the same method for other voltages, especially vDimm...

 

I think your memory timings, while very impressive, may be a bit tight for further overclocking and perhaps you should consider loosening to the following timings, in order:

 

2.5-3-3-6

2.5-3-3-7

2.5-3-3-8

2.5-4-3-7

2.5-4-3-8

2.5-4-3-9

2.5-4-4-8

2.5-4-4-10

3-3-3-8

3-4-3-8

3-4-3-9

3-4-4-8

3-4-4-9

3-4-4-10

 

* there is no Northbridge on the A64 platform, the equivalent NB architecture is basically inside the CPU, the chipset is basically the Southbridge