CPU ratio dropping and Clock speed dropping?!

[humphrey502690]

Hey i am starting a new build for fun with a BD FX 8140. This processor hasnt been very OC friendly.
First my VCore is pretty high..trying to get the highest possible OC on this thing i possibly can...
its on another Crosshair V-Z.
When running Prime95 for about 30mins into it my clock speeds drop along with my Vcore (slightly) and Ratio.
Currently its set at 4.53GHz With a Ratio of 21.5 and Bus is 210 with a Vcore of 1.4375 (which shows as 1.44v on HW)
When it drops it downclocks to 1.47GHz, Ratio 7.0 and Vcore to 1.428v for a min then upclocks back to normal OC. then repeats around every 6-7mins
My max temps hit about 72 and its under custom waterloop.
It takes around 1 hr to hit those temps and my usage stays at full load 100% the whole time.
Thanks!

 

[rowdymoody]

I was unable to find exact specs on the temperature threshold of the 8140, but the maximum temperature of an fx 8350 is 70, and anything over 60 on individual cores can make the cores unstable. In reality, it is probably best to try and keep cores below 55.

I am sure that the temp tolerances of the 8140 are similar to the 8350, your issues are probably due to thermal throttling. You are getting the CPU too hot.

 

[humphrey502690]

well i have also noticed that playing starcraft 2 its unstable within about 15 mins..
my last known good OC is 4.4GHz @ 1.428v 20.0 ratio and 220 Bus... and my temps hit 70ish with out any issues whatsoever

 

[rowdymoody]

Then I would just run it at 4.4ghz. There really won't be any difference between that and 4.5ghz. You wouldn't notice any improvement. running 4.5 over 4.4.

 

[humphrey502690]

i was finally able to get it boosted a little more.. i simply had too much on my voltage and it was getting to hot..
adjusting it to 1.400v and i got it up to 4.6GHz with a little tweaking so far prime stable for 2hrs.
very impressed with this little guy! 3.2GHz stock up to (so far) 4.6GHz!! thats a 1.4GHz OC! best ive had yet.
My temp got to 71.
Im most likely going to add a block on my board to see how much higher i can get it..
i kinda feel like i got a "golden chip"... -shrug- too bad it wasnt with my 9590 though lol

 

[humphrey502690]

i should keep lowering my voltage until it doesnt boot to windows correct?

 

[rowdymoody]

You don't have to lower it quite that far. Lower it until you become unstable, ie crashing during stress tests and such, this will help you fine tune where your voltage needs to be. When I find the voltage that I think is just right, I stress test for a few hours, and then check event viewer for WHEA errors. WHEA errors are an indicator of instability. They don't necessarily mean your pc will not run right with the overclock, matter of fact you can get whea errors and never have a problem with your overclocked chip. But if you are truly stable you will get zero WHEA errors during your stress testing.

Glad to hear you are getting it figured out, that is a pretty decent overclock.