Okie smokey.

I've recently 'managed' to get 64bit vista installed. I've gone through all the updates that I Can, up untill the point where it wants to install Service Pack 1, which is causing issues. However, that's not (yet) what this thread is about.

Basically, I've come accross a few BSODs that say that a "clock interupt was not recieved by a secondary proccessor." or words to that effect.

Basically, after some googling I've discovered that there is a design flaw in the 9600 (or rather, any phenom) in that the third core basically craps out when performing above certain speeds, causing the BSOD.

The 'solution' (other than to send it back to AMD, which I eventually will) is to underclock the third core to around 2ghz, thus it never reaches the stage where it craps out.

However, all these people who've recieved that suggestion have then just posted "I tried underclocking the third core and it worked a treat!" and I just can't seem to find a clear guide on how to underclock a single core out of 4.

I've found guides about overclocking etc - which I roughly get. I also found an official AMD utility for overclocking, however it's not compatible with my system.

If it helps, I'm running the latest availabe BIOS for the ASUS Crosshair motherboard.

So, short version How do I underclock a single core on an AMD Phenom 9600, connected to an ASUS Crosshair MOBO?

I hate computers.

Phenoms are tri-core, right?

Anyway, most likely to underclock, you're going to need to boot into your BIOS. Somewhere in there you'll have options to adjust clocks speeds, memory timing, voltages, all that jazz. I haven't personally messed with overclocking in years... well before the advent of multi-core processors. However, if it's possible to underclock a specific core, that's where it would be.

If you still have your motherboard manual, check out the section on the bios. It should give at least a little more info.

Yo, Mole here

The Phenom is Quad Core - or at least the version I purchased is. They've 're-released' the Phenom as a Tri-Core, which is actually the same CPU but with the faulty core disabled.

And yeah, I've been fiddling in the bios, but it doesn't make much sense to me! I'll have to dig out the manual and see. I think I can see how to overclock the entire set of chips, but not underclock just one.

More research is needed, but so far all my results come back unsuccesful.

ah, ok. Thanks for the clarification. I don't have any phenom boxes to play with, so I'm afraid I can't really help you.

hate to say it, but Intel chips are better anyway. Have been since core2 came out. If AMD can ever come back and deliver a high quality chip, I'll go back to them. I guess if I was building a low-power box I'd go with AMD too.