Trouble Overclocking with Epox EP-9NPA3ULTRA

[memnoc]

So I got an Opteron 146 to go with my new motherboard specifically so that I can overclock it a bit. I followed Zebo's instructions about isolating and consolidating and it turns out I can run 2.8 GHz stable at 280*10 (FSB*mul). However, I can't adjust my memory to anything close to 200. My memory isn't the greatest and isn't exactly matched:

512 PC3200 Corsair Value Select
512 PC3200 Buffalo CH-5 (i think)

When isolating I could get it above DDR400 to around 220MHz. Whenever I overclock, however, I have to keep the multiplier around much lower. Right now at 2.8GHz I can't run it higher than DDR200, so that's 140MHz memory. If i go higher my motherboard starts beeping. I have the same issue until I drop the FSB down to like 240 or so.

Is there a setting I'm missing some where? Using the latest bios.

 

[furballi]

Are you using a memory divider, like 166 or 133?

 

[memnoc]

yea, when running at 2.8GHz I have to set the memory frequency to 100 for it to boot. That gives me an effect 140MHz memory frequency since the FSB is at 280. I would think even with crappy memory I should be able to run it at anything under 200MHz. If I drop the FSB down to like 250 I still have to run the memory at way below 200MHz (by using the memory divider).

PS: I'm assuming the memory divider is the option that lets you select DDR200, DDR266, DDR333 etc.

 

[gfngfgf]

You know, I have 2x512MB Corsair Value Select on an Epox 9npa+Ultra, and I could never boot using the 133 divider. 100, 166, 200...all the others work fine (as long as the resulting memory speed is under around 220MHz). Not sure why that is, but for my overclock, it didn't really make a big difference so I never investigated further. BTW, I've got a X2 3800+ Manchester core.

 

[memnoc]

i guess they're just quirky motherboards. Anybody else have any ideas?

 

[Fallengod]

Its possible it just doesnt like value memory. I dont have that one but I do have the Epox 9npa+ultra mobo and I run a 166 divider no problem at 250mhz.

It sounds like you dont have 2 identical sticks of memory either. That usually isnt the best thing. Are you using dual channel mode? Might stick them in single channel mode to see if that does anything.

 

[memnoc]

I'm pretty sure it's the Buffalo memory. I ran them one at a time and the Corsair can go a bit over 200MHz and works with whatever divider keeps it near there. The Buffalo just doesn't like using dividers it seems - at least not at certain CPU frequencies. Is that typical of some RAM or is there something else wrong here?