fx 6300 OC Vcore huge drop

tony1-3-9

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Sep 2, 2014
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overclocking my fx 6300 @ 4.9ghz on gigabyte 78mlt-usb board, some weird voltages under core voltage, see pic look at vcore minimum, its dropping to 1.26 every few seconds but all cores still at 100%

2h2qi9u.png


Any ideas whats going on here? Definately not normal, This is only after 20minutes of stress testing small ffts in p95, why is it droppiin so low and why is it still stable???? A drop to 1.26v would surely cause cores to fail?
 
Solution
Unless your temps are going high, it's probably not throttling. FX CPUs throttle in the 70c range.

It is more likely severe V-Droop. That board does not have the VRM to support a high OC with high voltages.

From the manufacturer's site:
"4+1 Phase CPU Power design for AMD high TDP 125W CPU support"

I used a Gigabyte GA-970A-UD3P with 8+2 phase power and LLC adjustment in BIOS to hit 4.960 GHz stable on an FX 6350. You need a really good power circuit and chipset to get stable voltages for an OC.

Also for testing, I just use AMD Overdrive. It stresses the CPU just fine with a fairly diverse workload.

Also, a good idea is to read the FX tuning guide from AMD and the Bulldozer OC guide...

tony1-3-9

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whys it throttling? Multiplier to high or just reached its limit?
 

jdcranke07

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I have an 8350 that is clocked at 4.6Ghz with a slight Bus OC as well and I'm no where even close to that Vcore. Your CPU is not meant to be clocked at 4.9Ghz unless you have a LN2 setup which I'm assuming you don't. And even then it would still be killing your CPU at 1.5V of Vcore.
 
Unless your temps are going high, it's probably not throttling. FX CPUs throttle in the 70c range.

It is more likely severe V-Droop. That board does not have the VRM to support a high OC with high voltages.

From the manufacturer's site:
"4+1 Phase CPU Power design for AMD high TDP 125W CPU support"

I used a Gigabyte GA-970A-UD3P with 8+2 phase power and LLC adjustment in BIOS to hit 4.960 GHz stable on an FX 6350. You need a really good power circuit and chipset to get stable voltages for an OC.

Also for testing, I just use AMD Overdrive. It stresses the CPU just fine with a fairly diverse workload.

Also, a good idea is to read the FX tuning guide from AMD and the Bulldozer OC guide.

http://www.overclock.net/t/1140459/bulldozer-overclocking-guide-performance-scaling-charts-max-ocs-ln2-results-coming

http://sites.amd.com/us/Documents/AMD_FX_Performance_Tuning_Guide.pdf
 
Solution

tony1-3-9

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Sep 2, 2014
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ok isee, i think i will be in the market for a better mb then, so what i have done is went back to my old oc of 4.75, i had to set vcore at 1.52 in bios under full load in p95 my vcore reads 1.440 and temps never go over 47 degrees which i think is ok for this chip would any of you recommend this board?
-gigabyte 970a-ds3p
i dont have a big budget so anything around 60 quid would be my limit for a new board. Thaks again for your posts guys.
 


UD3P is better. Just watch for it to go on sale. It's a very good 970 board.