Hi, I, since I bought the hd 7850, had been using a vga monitor. I used a vga to dvi converter to connect it to my graphics card, as it has no vga port. And everything was fine. The idle core clock 300 MHz and memory clock 150 MHz as it should be.
I sold that monitor and from yesterday started using a DVI monitor and noticed the memory clock doesn't go down at idle state. My stock memory clock is 1250 MHz. So it remains at 1250 MHz at idle too. I've changed the memory clock and noticed the idle memory clock changes the same way too. That means as soon as i make the memory clock 1260 MHz, the idle memory clock goes to 1260 MHz too.
Due to this fact, the idle gpu temperature and idle voltage also have increased a bit.
My monitor is LG W2243T-PF @ 1920x1080 @ 60 Hz.
Also, I'm using a single link DVI-D cable though the female DVI ports in my graphics card and monitors are both dual-link. But that shouldn't be any issue since I'm not going over 1920x1080. In fact that's the highest resolution the monitor supports.
No such problem has been noticed with the core clock. It's idle clock was 300 MHz when i used VGA monitor. now with DVI, its 400 at idle, but that's okay since it remains constant at idle no matter how i tweak the core clock.
Edit: I found some new things. The idle core clock hasn't gone from 300 to 400 due to the change of monitor. It has actually gone up to be compatible with the high idle memory clock. As long as the memory clock remains under 1200 MHz at idle(it doesn't remain so by default as I said. I have to underclock it), the core clock at idle remains 300 MHz and as the memory clock crosses 1200, the core clock rises to 400 MHz. That makes sense, there might be some minimum core to mem clock ratio set by AMD for this card.
So because my idle memory clock is stuck at 1250 MHz(or whatever I use with any tweaking tool), so the idle core clock has gone to 400 MHz too.
So the main problem is in the idle memory clock.
Edit 2: I found out in idle state the card uses the 2d settings. Now I customized the 2d settings using ASUS GPU tweak and noticed the idle memory clock doesn't change when i change 2d settings memory clock. It just remains constant whatever value I put and apply. So the gist of the problem is: Somehow the idle memory clock is listening to the 3d settings, not the 2d one!
The core clock is acting normal. The idle core clock becomes what value I put in 2d settings core clock.
I also wonder if the 12.11 beta driver is causing the problem. I installed the beta driver one week ago. So I'm not 100% sure, if the memory clock was problematic with the beta driver and older VGA monitor too. But I seem to remember things were okay with the old monitor.
Solution of this problem will be highly helpful. Thank you.
Edited by Driimit - 11/11/12 at 11:26pm
I sold that monitor and from yesterday started using a DVI monitor and noticed the memory clock doesn't go down at idle state. My stock memory clock is 1250 MHz. So it remains at 1250 MHz at idle too. I've changed the memory clock and noticed the idle memory clock changes the same way too. That means as soon as i make the memory clock 1260 MHz, the idle memory clock goes to 1260 MHz too.
Due to this fact, the idle gpu temperature and idle voltage also have increased a bit.
My monitor is LG W2243T-PF @ 1920x1080 @ 60 Hz.
Also, I'm using a single link DVI-D cable though the female DVI ports in my graphics card and monitors are both dual-link. But that shouldn't be any issue since I'm not going over 1920x1080. In fact that's the highest resolution the monitor supports.
No such problem has been noticed with the core clock. It's idle clock was 300 MHz when i used VGA monitor. now with DVI, its 400 at idle, but that's okay since it remains constant at idle no matter how i tweak the core clock.
Edit: I found some new things. The idle core clock hasn't gone from 300 to 400 due to the change of monitor. It has actually gone up to be compatible with the high idle memory clock. As long as the memory clock remains under 1200 MHz at idle(it doesn't remain so by default as I said. I have to underclock it), the core clock at idle remains 300 MHz and as the memory clock crosses 1200, the core clock rises to 400 MHz. That makes sense, there might be some minimum core to mem clock ratio set by AMD for this card.
So because my idle memory clock is stuck at 1250 MHz(or whatever I use with any tweaking tool), so the idle core clock has gone to 400 MHz too.
So the main problem is in the idle memory clock.
Edit 2: I found out in idle state the card uses the 2d settings. Now I customized the 2d settings using ASUS GPU tweak and noticed the idle memory clock doesn't change when i change 2d settings memory clock. It just remains constant whatever value I put and apply. So the gist of the problem is: Somehow the idle memory clock is listening to the 3d settings, not the 2d one!
The core clock is acting normal. The idle core clock becomes what value I put in 2d settings core clock.
I also wonder if the 12.11 beta driver is causing the problem. I installed the beta driver one week ago. So I'm not 100% sure, if the memory clock was problematic with the beta driver and older VGA monitor too. But I seem to remember things were okay with the old monitor.
Solution of this problem will be highly helpful. Thank you.
Edited by Driimit - 11/11/12 at 11:26pm




