What is a good temp and fan speed?

[pizza]

Hello,

Have sapphire 7950s reference design. What is the max fan I should run these cards on? Do the fans die easily? What temps should I aim for? for longevity?

Thanks

[bcpokey]

Lower is always better, sadly with the reference blower cooler, you will need to choose between higher temps or higher fan speeds.

I don't recommend these as your primary GPU, I've had 2 so far, and both have artifacted under high stress. If you have good airflow and reasonable ambient, I'd say 50% fan speed and 77C is reasonable, for longevity of both. You can go higher, but as I said they seem fragile, and there's not enough long term data to really know what will happen.

[Protagonus]

Here's a page that shows lifespans of led and capacitors, relative to temperature.  IC's will have a similar relation of lifespan vs. temp.  Just scroll to the 2 images.
http://ele-tech.com/html/relation-of-the-electrolytic-capacitor-and-life-span-of-led-lamps-and-lanterns.html

For me, I guess I try to stay at or under 70C for core and at or under 80C for vrm's.  I would assume this to work out close to half the maximum "theoretical" life.  (e.g. 75C @ 70% flux on LED chart for comparison)

[pizza]

Also, does anybody know if we can underclock our memory on these? I set it in trixx but I see in gpuz that it's always at 1250

[induktor]

Also, does anybody know if we can underclock our memory on these? I set it in trixx but I see in gpuz that it's always at 1250

Yes but not all combinations works, for example in my card, If I run GPU at 925 Mhz, mem must be 775 Mhz, any lower than this and it will jump to default 1250 automatically, If I lower GPU to 900 Mhz, MEM can be 750 Mhz not lower (this is on sapphire 7950 3GDDR5, dual fan) settings with TRIXX, at 925 my
temps are 63 C with 75% fan speed.  (fans are a lot cheaper to replace than a VRM or worse (mem, gpu chip))

[pizza]

Also, does anybody know if we can underclock our memory on these? I set it in trixx but I see in gpuz that it's always at 1250

Yes but not all combinations works, for example in my card, If I run GPU at 925 Mhz, mem must be 775 Mhz, any lower than this and it will jump to default 1250 automatically, If I lower GPU to 900 Mhz, MEM can be 750 Mhz not lower (this is on sapphire 7950 3GDDR5, dual fan) settings with TRIXX, at 925 my
temps are 63 C with 75% fan speed.  (fans are a lot cheaper to replace than a VRM or worse (mem, gpu chip))

Thanks will try it out

[Bitsaurus]

You should be able to underclock the memory all the way down to 100, use MSI AB.

[pizza]

You should be able to underclock the memory all the way down to 100, use MSI AB.

will try that instead of trixx.

[pizza]

also before i was able to get high overclocks of about 1250 on all the cards, but after a few crashes now i cant run those clocks anymore. Would reflashing the gpu bios help? or is it a hardware malfunction?

[YipYip]

Here's a page that shows lifespans of led and capacitors, relative to temperature.  IC's will have a similar relation of lifespan vs. temp.  Just scroll to the 2 images.
http://ele-tech.com/html/relation-of-the-electrolytic-capacitor-and-life-span-of-led-lamps-and-lanterns.html

For me, I guess I try to stay at or under 70C for core and at or under 80C for vrm's.  I would assume this to work out close to half the maximum "theoretical" life.  (e.g. 75C @ 70% flux on LED chart for comparison)

Excellent charts dude ...thanks

[ryantc]

or you can allow the temp hell high and hope video cards will die out within the warranty period......

[mokahless]

In my experience, fans die easily, depending on quality, at high RPMs for extended periods of time. I wouldn't recommend over 90% 24-7 if you have to. That said, fans and coolers are a lot easier to replace than a chip not under warranty.

[pizza]

In my experience, fans die easily, depending on quality, at high RPMs for extended periods of time. I wouldn't recommend over 90% 24-7 if you have to. That said, fans and coolers are a lot easier to replace than a chip not under warranty.

Id rather kill the card 2yrs warranty and have them come with new fans lol, or an upgraded model lol

Im running 70% fans, that should be fine right?

[PCMiner]

I'm running this card for a mining rig right now and it's at a constant 85% fan and about 74c.  Should I down clock it?  Noise isn't the issue, but if it's likely to blow the fan running like that I'd rather save the hassle.
I also have this card this card running in another machine super overclocked and it it runs the same temp but with a lower fan speed, around 65%.

Side note, if I was going to combine these cards into a single machine, that has to be upright, (cards will be on top of each other) which of the two cards should be the bottom vs the top?  I have another machine with the 3L card (second one I listed), should I put both 3L's in one machine and have the 4L (vents out the back fan) in it's own rig?  I have risers coming, but thanks to long shipping times they won't be here for a few weeks.