Safe Phenom northbridge voltage

[SlowSpyder]

I'd like to try and give my northbridge a nudge and see if I can't get a bit more out of it. Right now I run the CPU at the stock 2000MHz IMC/L3 frequency. I'd like to bump that up if possible. From what I've seen the Phenoms get a nice performance boost as the L3/IMC are bumped up in speed. I'm not looking for the absolute most I can get out of it, but a nice, safe speed bump that doesn't push the temps too high. Anyway, I have the ability to add voltage to my northbridge in the BIOS, but I can't really find anywhere what the safe range is. Right now I have it set to auto. Does anyone know what the stock voltage on the IMC is? CPUz shows the CPU core voltage, but not the IMC voltage.

Right now the processor is more then fast enough for me, but I'm trying to run a few benchmarks and would like to see what kind of difference there is at a given CPU frequency with different IMC/L3 frequencies.

Any help is appreciated.

 

[cusideabelincoln]

Well, it depends on the motherboard, motherboard chipset, and cooling. I think it would be safe for you to assume that the lowest voltage offered is probably the "stock" one, but again I don't know what board you're using.

If you've read (or look up) overclocking reviews you will probably find some mention of safe northbridge voltage and HT overclock for your Phenom.

 

[SlowSpyder]

Originally posted by: cusideabelincoln
Well, it depends on the motherboard, motherboard chipset, and cooling. I think it would be safe for you to assume that the lowest voltage offered is probably the "stock" one, but again I don't know what board you're using.

If you've read (or look up) overclocking reviews you will probably find some mention of safe northbridge voltage and HT overclock for your Phenom.

I did try and find it using Google, but many reviewers simply use the unlocked multiplier for their overclock. Most just say what the final clocks are they settled on (even if they do use the northbridge) but don't mention voltage. If they do mention voltage all I've seen is CPU core voltage.

I'm using an MSI K9A2 Platinum (790FX w/SB600). I have the option for auto, then actual voltages I can choose. I can't just choose the next voltage up from 'Auto' as I'm pretty sure that there are under-volting options there as well.

 

[cusideabelincoln]

Ah, I think the simplest solution would be to install AMD Overdrive.

 

[Rhoxed]

I also have the MSI K9A2 Platinum, and with a 235HT OC (NB and HT at 2,350) i keep the NB voltage at 1.125 and the HT voltage at 1.150

 

[SlowSpyder]

Originally posted by: Rhoxed
I also have the MSI K9A2 Platinum, and with a 235HT OC (NB and HT at 2,350) i keep the NB voltage at 1.125 and the HT voltage at 1.150

Excellent, thank you for the voltage numbers. Did you ever do any kind of comparrison with the 9850 at 3.0GHz/2.0GHz IMC vs. 3.0GHz/2.35GHz IMC? I imagine there is a nice bump in the performance.

 

[SlowSpyder]

Well, I tried those settings (235HT w/1.125v on the NB and 1.175 on the HT - I don't see an option for 1.150 in my BIOS) and it's a no go. On attempting to boot I hear the fan in my video card peg itself at 100% and nothing else happened. I powered it down and reset the CMOS battery, and am back at square one. I'm guessing I have to lock down the PCIe frequency or something? Any idea?

*edit - Also, I did have my memory divider set up so my memory was at just under 800Mhz, so that shouldn't be an issue. Good thing this processor has an unlocked multiplier, I'm not sure I'd be smart enough to get any overclock otherwise.

 

[cusideabelincoln]

Yeh, you better lock down the PCI-E frequency and you should gradually increase the HT.

 

[Sylvanas]

I have an X2 but I guess I will chime in anyway- I have my NB voltage/HT voltage set at 1.250 in the BIOS which actually seems pretty conservative.

I'm guessing I have to lock down the PCIe frequency or something? Any idea?

PCI-E frequency is not adjustable via the BIOS unless you are running the BETA that I am (got it from MSI, it is linked to in the XS K9A2 Plat thread).

This is the K9A2 Plat thread that is perhaps the best source of information about Phenom on the net, have a look through the last few pages for 9850BE results. Here is a thread about adjust NB voltage on the K9A2 Plat, it is not 'officially supported says MSI but it is available in the 1.1beta BIOS (I think thats the one....thats going back a while) or as you can see from that link the official bios by adjusting the HT ratio which actually affects NB speed. Enjoy your K9A2 Plat- it is an awesome board .