- Feb 11, 2014
- 4
- 0
- 10,510
Hey guys:
Thank you to whoever reads this cos It's a wall of text.
My specs are:
ASrock z68 Gen3 Extreme3
Sandy bridge I5 2500K (100x43) stock voltage
600W Aerocool Strike X
8 GB GSkill Ripjaws X DDR 1600 CL9
2x SSD Crucial M4 ** Samsung 840 Pro
2x Sapphire 7870 OC edition
VBIOS 015.025.000.002.000000 on both 7870 cards
Catalyst 13.25
- I bought a 7870 OC edition in May 2012 and ended up with this card:
http://www.sapphiretech.com/presenta...pid=1487&lid=1
- Then bought a second 7870 OC Edition card on October 2013 (while the first one was being attended by Sapphire due to the black-screen issue. Thanks Sapphire). But I received this card:
http://www.sapphiretech.com/presenta...n=&lid=1&leg=0
I'm aware that there are video output, size and PCB distribution differences. But there are certain differences that might be limiting my ability to overclock both cards in Crossfire.
To start with, TechPowerUp states that (The latter 7870 OC edition) runs at different memory clock speed (1200mhz instead of 1250mhz). Could possibly be an error on their side:
http://www.techpowerup.com/gpudb/b66...dual-x-oc.html
However:
I started having jerky images and framerate issues when I first attempted crossfire with old 13.11 Catalyst drivers. But solved the problem by backing up the most recent BIOS from one of the cards and flashing the second one with it. I also updated Catalyst drivers to 13.25 to make sure everything was up to date.
While I am extremely happy to play Crysis 3 on Very High at 1920x1080 with nice and stable framerates I wanted to see if I could get some more performance on 3dmark11 (As I've seen overclocked 7870's get an extra 10% punch on a few benchies). And so attempted overclocking using TRIXX.
My problem is that any attempt to use TRIXX or CCC's overdrive (Clocking upwards without or with voltage modifications ends up in failure. Even for a slight 25 mhz increase over GPU clock speed).
I fact I tested yesterday TRIXX and by just appliying the same voltage to both cards 1250 mV I end up with artifacts on screen.
I also attempted to only overclock the primary card (Which is the one released on November 2012) and It worked. No artifacts or crashing. But there was no performance increase, which has been stated in several tutorials I went through recently.
Finally... I have seen on a different thread that there are differences in stock voltages between both cards:
https://www.sapphireforum.com/showth...tage-at-1250mv
Any of you have experience or refferences regading Crossfire OCed setups?
Anything else I should consider?
Could the two cards have too many differences to be able OC them together while in crossfire?
Thank you.
Thank you to whoever reads this cos It's a wall of text.
My specs are:
ASrock z68 Gen3 Extreme3
Sandy bridge I5 2500K (100x43) stock voltage
600W Aerocool Strike X
8 GB GSkill Ripjaws X DDR 1600 CL9
2x SSD Crucial M4 ** Samsung 840 Pro
2x Sapphire 7870 OC edition
VBIOS 015.025.000.002.000000 on both 7870 cards
Catalyst 13.25
- I bought a 7870 OC edition in May 2012 and ended up with this card:
http://www.sapphiretech.com/presenta...pid=1487&lid=1
- Then bought a second 7870 OC Edition card on October 2013 (while the first one was being attended by Sapphire due to the black-screen issue. Thanks Sapphire). But I received this card:
http://www.sapphiretech.com/presenta...n=&lid=1&leg=0
I'm aware that there are video output, size and PCB distribution differences. But there are certain differences that might be limiting my ability to overclock both cards in Crossfire.
To start with, TechPowerUp states that (The latter 7870 OC edition) runs at different memory clock speed (1200mhz instead of 1250mhz). Could possibly be an error on their side:
http://www.techpowerup.com/gpudb/b66...dual-x-oc.html
However:
I started having jerky images and framerate issues when I first attempted crossfire with old 13.11 Catalyst drivers. But solved the problem by backing up the most recent BIOS from one of the cards and flashing the second one with it. I also updated Catalyst drivers to 13.25 to make sure everything was up to date.
While I am extremely happy to play Crysis 3 on Very High at 1920x1080 with nice and stable framerates I wanted to see if I could get some more performance on 3dmark11 (As I've seen overclocked 7870's get an extra 10% punch on a few benchies). And so attempted overclocking using TRIXX.
My problem is that any attempt to use TRIXX or CCC's overdrive (Clocking upwards without or with voltage modifications ends up in failure. Even for a slight 25 mhz increase over GPU clock speed).
I fact I tested yesterday TRIXX and by just appliying the same voltage to both cards 1250 mV I end up with artifacts on screen.
I also attempted to only overclock the primary card (Which is the one released on November 2012) and It worked. No artifacts or crashing. But there was no performance increase, which has been stated in several tutorials I went through recently.
Finally... I have seen on a different thread that there are differences in stock voltages between both cards:
https://www.sapphireforum.com/showth...tage-at-1250mv
Any of you have experience or refferences regading Crossfire OCed setups?
Anything else I should consider?
Could the two cards have too many differences to be able OC them together while in crossfire?
Thank you.
Facebook
Twitter
Instagram