Accessing CPU multiplier in BIOS

[633210]

Hi everyone,

First-time builder, first-time overclocker here. I've read the stickies and searched the site, but still have a question that probably has an obvious answer. So my apologies in advance if this has been answered before:

I wanted to take a shot at manually overclocking on my system, rather than using the automatic tools available, since I'm a bit of a control freak. The mobo/CPU/RAM are ASUS M4A87TD EVO, Phenom II 955 BE, and G.Skill Ripjaws 2x2 GB 1600, respectively. The processor is touted as having an unlocked multiplier, of course, but I can't for the life of me figure out where in the BIOS I can adjust it! I've taken the liberty of adjusting the CPU Bus frequency to 215, which, according to CPU-Z has resulted in a gentle overclock to 3.451 GHz. The system seems to be stable, but I'm just totally unsure whether I'm doing it right. Something else of note is that this changed the RAM frequency to 862.9 from its default 800. Possibly unrelated note: I was able to manually set the RAM timings to 7-8-7-24 per manufacturer's specs without any issues.

Thanks for your time.

 

[jprahman]

If you want to check if your overclock is stable you'll want to run prime95. It will alert you if any errors are encountered, indicating that your overclock is unstable. You also need to keep track of your temps. RealTemp is a good tool for that purpose.

To increase the CPU multiplier the option you need to look for is called CPU Ratio. It should be located in the AI Tweaker tab. Here is a link to the page where you can download the manual for your motherboard where all the info you'll need will be: Manual. Just go to the download tab and enter your operating system. It'll give you a list of files, at the end of the list if a set of manuals, one of which is the english one.

 

[633210]

If you want to check if your overclock is stable you'll want to run prime95. It will alert you if any errors are encountered, indicating that your overclock is unstable. You also need to keep track of your temps. RealTemp is a good tool for that purpose.

To increase the CPU multiplier the option you need to look for is called CPU Ratio. It should be located in the AI Tweaker tab. Here is a link to the page where you can download the manual for your motherboard where all the info you'll need will be: Manual. Just go to the download tab and enter your operating system. It'll give you a list of files, at the end of the list if a set of manuals, one of which is the english one.

Thanks! This all looks great. I tried running Prime95 at the overclock listed above, and failed within a minute. I went back into the BIOS and set everything back to the default stock settings, tried Prime95 again, and got the same results. What would cause the stock settings to be unstable?

 

[jprahman]

BTW, welcome to tom's.

Either you have bad RAM or your motherboard is incorrectly auto-configuring your settings. There's also the worst case scenario that your CPU is bad, but I doubt that. Can you list all your settings and voltages for both the CPU and RAM, even the ones that you motherboard is automatically configuring?

You can run Memtest86 to rule RAM issues, stemming from either instability or bad modules.