Widescreen Gaming Forum

Has anyone else noticed this ?

In single screen when not under sufficient load, i.e windows desktop, or playing a game that doesnt tax the card i.e. BF2, the 5870 underclocks itself on both core and memory, i.e at the moment typing this i'm running at about 157 core, 300 mem. This obviously decreases consumption / heat and helps the card run very quiet as the fan speed can drop right down.

If i run an 3x Eyefinity group, at desktop the memory never underclocks, the core drops down though. This keeps temps up and requires much more fan to keep quiet.

Is this a driver bug ( 9.12 ) or does eyefinity need full speed memory all the time ?

Thanks

This is normal behaviour. Memory clock switching is done within a VBLANK timing of the monitor, so you do no notice the clock changes; in multi-panel scenarios the panels are likely to have different timings so they will have different VBLANK times in which case if you did switch memory then you would see a flash. When more than one panel is enabled, so that a screen flash doesn't occur the memory clock is kept constant.

The engine clock (and voltage) does still go down (though not as much as in single panel mode).

I still get the same whether EF or extended:
GPU1: 725/1000 (ha it is supposed to be the pre-OC'd sapphire but it stays at stock!)
GPU2: 157/300

I haven't used a single screen yet that often to check. Still uses less Watts than my 2xGTX280s (sold on TradeMe for just under the price of my 5970- WIN!) when both in slow mode :)

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Dipping bags at Mach1.9

thanks for the response, am fairly sure its not underclocking the memory at all ( core is ok ) , monitoring via msi afterburner and its not dropping at all from 1200 at all when in eyefinity( or 3 screen extended), as a result have to run the fan at 30 ish to keep temps somewhere under 70 ish

as soon as i change to single screen i can run the fan at 22 and get temps of 50 etc

Hi am am david I got my 2 5870 Radeon HD and i have been playing with them and after a week I started to notice that I am running at 157 core, 300 mem on my first GPU and my second GPU is at 1200 core, 400 mem and when I am in games my 2 GPU does all the work when the first one is doing nothing and my mem and core clocks don't change. for ex: Dirt 2 about 20 fps and about a week ago I was getting 60 fps. I use after MIS Afterburner to overclock to 850 core, 1250 mem but not going above 75 C. I have crossfire active but it does not seem like my first card is doing anything.

PLZ help!