Opterons and Dividers

[Postal Dude]

Can using dividers on an opteron or any other A64 type processor limit its overclock abilty? I remember reading that opterons in particular dont like Memory dividers. But not knowing how they actually afect the processor. IS hindering overclock a symptom?

[[timko]]

Where exactly did you read that Operton's don't like having dividers being used?

Dividers help overclock in most cases because it allows the user to run a higher HTT whilst leaving the RAM at a lower Mhz. Particularly useful if users are limited by the multiplier and/or their RAM is incapable of high Mhz.

There are plenty of people on these boards, myself included, that run dividers on our Opterons. Take a look at this recent post for instance...

http://www.xtremesystems.org/forums/showpost.php?p=1269684&postcount=65

...Thorlite is running a divider of 133 (also known as 2/3) with his Opteron 170 where his HTT is at 320Mhz and his RAM is at 213Mhz. If that doesn't tell you that dividers are ok with opterons then I'm not sure what will :)

[mrlithium]

Using dividers is only helpful when your RAM mhz speed is not high enough and it is limiting your overclock. If you reach a wall at 260 * 10 with PC 4000 RAM that is because your ram is running 10mhz over spec (260 compared to 250). If you drop it down to the 11:12(183mhz) or 5:6(166mhz) divider, your RAM will really be running SLOWER until you adjust the FSB to compensate. Then just increase the FSB to like 270-280, or higher, and your RAM will approach its original rated speed.

if you have an opteron 146 and ddr500 ram. some sample numbers and a good setting is 275 * 10 = 2750 mhz. Use 11:12 (183) divider, RAM runs at 250mhz.
You may ask if now the 250mhz ram on the 11:12 divider is slower than the 250mhz ram at 1:1. The answer is no, the athlon64/opterons are able to divide the memory frequency with very little to no loss of performance. However try to stay away from using the lower dividers if you have a choice, 2:3(133mhz) is sorta a performance degradation, but if thats what it takes for your CPU to break a certain barrier (2.6,2.7, 2.8ghz whatever) then you should use it, because the little performance lag is much outweighed by raw CPU clock speed.

[HARDCORECLOCKER]

:D No confirmation here.............

http://img355.imageshack.us/img355/8767/15527wn.jpg

:toast:

[Postal Dude]

oh crap. my opteron is crapping out at 2.7 using really high volts (1.55) All the while iv been using the 180 divider (not 183) Thought that this might have sumthin to do with it. Looks like i just got a dud cpu :(

[Highland3r]

Mines the same, doesnt seem to like dividers at all...
Might be worth having a play with alpha timings though, see if those don't help at all....

[Diverge]

Mine just don't like certain dividers.. ex, locking up after post. Not all dividers, just certain ones.

[krampak]

200:180 doesn't work on my 148. 200:166 runs perfectly.

[bachus_anonym]

All dividers, down to div133 work on my Opteron 146 with no problems at all... Various memory tested as well... At least up to 360HTT :D
Sometimes, playing with Drive and Data Strenghts as well as MAL and RP is needed to get dividers going... Everyone should try that before concluding that their Opteron doesn't like dividers :fact:

[HARDCORECLOCKER]

:D Hey bachus my friend - BTW I remember owing U a 32M with my FX........, watch #4 and You have one with my Opty..........;)

:toast:

[kiwi]

I had venice that did not like 166/180/200 dividers but only at htt >300. I can't remember problems with other chips though. Also you might have probz if cpu temps are very low, famous coldbug :/ This is why FX is preferred :)

[Eldonko]

All 3 of my optis have worked with 183, 166, and 150 dividers fine (on Expert). I think any problems may be memory/mb compatibility related.

[Rickster_64]

What motherboard are you using? Did you try an SD or Venice in the same board with no issues? My opty worked fine @ 2900/240/480 in my K8N NEO 2 Plat, but won't go above 2.8 and 230/460 with this EVGA NF4 SLI. Try another non Opty, and use the 166/133 dividers to rule out compatibility issues with the odd (**) ones.

[MaRtIe]

i have to use a divider.. 133

my tccd sucks so i keep them around 200mhz 2-2-2-5

[ben805]

My 170 Opteron with Ce-6 ram couldn't boot into windows with divider 133 or 140 regardless what memory setting I used, but with UCCC ram all dividers work just fine....go figure :D

[003]

200:180 doesn't work on my 148. 200:166 runs perfectly.
Same on one of my 146's.