• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

Hey guys I have trouble OC'ing my Sapphire 6870 1GB w/ Dual Fans

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.

Akhil

New Member
Joined
Feb 12, 2012
Hi I'm new to this forum and I was wondering if I could get some help plz. :) The problem is quite simple, my 6870 is not oc'ing well. I can get it stable at 945mhz core clock and 1150mhz memory clock. And this isn't even with stock voltages. I actually have to bump it all the way to 1.195 V before it runs stable. I use OCCT as a stability tester as it's pretty good at finding all possible errors. Not only that but if increase the clocks any higher without changing the voltages, not only are my temps high but I end up with artifacts. SOO my question to you guys is:

A) Is this normal?
B) What am i doing wrong?
C) Is the card defective?

I even changed the fan profile to amp up the cooling of the GPU, yet the temps are still reaching 82*C on OCCT with the clock speeds and volts mentioned above. Why can't I overclock any higher even though a lot of other people are able to get to 1000mhz core clock and 1200mhz memory clock on STOCK VOLTAGES!?!?! :shock: And the other minority can at least reach around 970mhz on stock voltage. I have to increase my core voltage just to OC my core clock to 945mhz. :-/ I'm not quite sure what on earth is going on. My computer seems to be well cooled as my CPU doesn't even reach 50*C on full load.

My specs:
-CPU: AMD Phenom II X4 955 @ 3.9GHz OC'ed using CCC CPU Overdrive
-Case and Fans: CM HAF 912 w/ two 120mm CM sickleflow fan intakes in front, stock 120mm intake on side case, 200mm CM megaflow exhaust on top and stock 120mm exhaust on back. Seems to me as cooling is sufficient :-/
-CPU Cooler: Corsair A50
-GPU: Sapphire Radeon HD6870 w/ Dual fans (DiRT 3 version)
-PSU: iCAN 600W which I'm pretty sure is more than enough even for Crossfire
-M/B: ASUS M4A785TD-V EVO
-OS: Windows 7 64-Bit
-RAM: 2x4GB DDR3 in dual channel

I've used 4 different ATI CCC drivers, no difference from any of them including latest 12.1.

So, I think I've put plenty of info and detail. :p This is my first time using a PC forum and I really need help. Hope you guys have any advice or suggestions. THANKSSSS :)
 
1. Silicon lottery and overclock is all about luck, I had a 4870 that the core wouldn't budge past 800mhz.

2. Try running some games/ other stability programs kombustor.. Thermals are going to be higher when stability testing than in games. Are you using trixx to overclock as thats what I do and I disable overdrive in ccc .
Try heaven for a realtime test.

3. Lot's of people getting 1000 core on stock volts being 1.175v, I don't believe that to be true. I think you need around 1.225-1.26v to get to 1000 core and then the power consumption + heat for the little fps gain makes it pointless.

4.You're not going to notice a huge difference between the clocks you are at now and at 1ghz. I'd monitor your temperatures during a gaming session with your card at standard clocks and v-core, to see if the temps are within spec and then compare to your overclocked settings.
 
Back