Hi, I just bought a Sapphire 7970 and installed the latest drivers, but this is what happen: For few seconds the VGA switch from low to high clock (like when gaming) and then return to low clock, all of this during normal desktop activity, like surfing on internet, The second problem is that the VGA emits a strange noise (like a whistle) under load, and I noticed that when it emits this sound I can see the PWM backlight flickering clearly. Any help would be appreciated, thanks.
Clock switching during regular activity is normal. Browsers use hardware acceleration. Windows Aero too. That noise is coil whine probably. Annoying, but not a defect. If you want, might try to return it.
Yeah in conclusion you have a totally normal working card. If you're playing something try turning on V-sync, that might fix it. Or setting an fps cap in MSI Ab at 60 fps.. also might take away the coil whine. Otherwise, it's normal. So no worries.
Actually the noise was the coil whine you were talking about (tried with Civ5: no noise with V-sync activated, noise without it). Never heard about this, thank you guys. About the "clock switching" during desktop activity, I disabled HW acceleration in my browser, but it could be Windows Aero as you said. I'll try to reinstall the drivers and see what happen.
the coil whine happens when the gpu outputs crazy fps. for me it's noticeable at over 1000fps. this can happen in game menus. in these games I just cap the framerate to 200 in msi afterburner and that fixes it.
