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hey guys

just installed a second gtx780 which resulted in temp increase. now vga1 is 83c and vga2 is 65c and fan speeds are 100%. I read that fan speed percentage 100% is only meant for a short period use, so this could result with my fans getting damaged. what do you think? And do you run your fan speeds at 100% ? How long has it been?

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100% is a fan killer. try 90% for the hot one and 85% for the cool one.   if your temps stay under 88c you should be okay.


these are subject to variation some cards can run at 92c long term some cards can't.  if the fans pick up speed and you are pushing 92c you need to figure out how to add more fans for cooling

thanks man;

currently running cudamanager, used to run 100% fan speed when one of the cards reachs 80C (even though 780 has a max operating temp of 95c according to nvidia) changed the settings to interactive and increased the warning temp to 83c. Now fan speeds 70%/60% and temp 82c/75c.

If you undervolt your cards then it'll run a lot cooler, and you'll be able to run the fan longer.

this also true but some cards are voltage locked .

to op if your card allows for voltage change try just a little less volts say your stock is 1.112v   try 1.085v  if stable  for a day drop it to 1.075v.

under volting  and under clocking just a little can really help in watts per hash rate.  and of course the card will last longer.

I had hd7970 's run 400 days 24 /7 under clocked/undervolted just a little bit and they still work fine.

I wouldn't go above 75%, but it all depends. Some cards "love" high rpm, some don't.

We run all of our fans at a flat 80%. Seems to be a good compromise between good airflow, and not killing the fans.

Tried using 80% fan speed and about 6 out of 20 fan died after 3 months.... is it because of the sapphire brand I am using?

I am running my Sapphire HD7950 at 85% fan speeds. Does that mean I should be worried, too?

Different manufacturers have different issues, and will invest different amounts into the quality of their fans. I know currently MSI has several issues with their fans. I've used the Gigabyte WF3 coolers, and never had an issue with the fans.

Thanks. I live in warm climate, so scrypt mining on my Sapphire 7950 card runs quite hot. If I try to mine with its full capacity (600+ khash/sec), then it goes above 90˚ C even with the fan running above 90%

So I am undervolting it to run at 500 khash/sec which keeps it below 75˚ C and the fan spins at about 80%

my fans for my 2 nvidia cards are currently at 60 and 67%, which are at 1000khash/sec instead of 1300kash/sec. My amd cards are running ate 75% fanspeed but I placed a 16in house fan to help cool them down. I think they are fine now.

I've been running my 8 7950's at 100% for 12 months now and not a hiccup to be had. But as with any consumer product ever made, each individual card, even in the same series, is slightly different with varying weaknesses and strengths. Perhaps I've been lucky. It's incredibly simple to just buy a new fan if one were to burn out. You can even take the chance to upgrade to a more powerful fan if you want.

Which brand are your 7950 cards?

This^

Sapphire fans are complete shit.  All my cards are Sapphire and all of the fans have died in under a year using 100%.  Now I use 80% so we shall see.

The expected lifetime of any fan, regardless of the brand, is likely measured in months if it is continuously running at maximum speed.

Sapphire 7950.  The 100352-4L model specifically.  I've had them overclocked since December with my core at 1050, my memory at 1700,and my voltage at 1068.  Out of 8 cards, only two dont like an overclock and I even run them at a slightly higher 1075 voltage.  Otherwise those two cards will crash my drivers for whatever reason.  It could be my drivers, but I haven't really cared about getting an extra 200 khs for the effort of troubleshooting past what I've already done.

I would agree with that if we're talking about stock fans.  But if you buy a quality fan, and properly maintain it, you're talking many years of good use so long as you don't end up with a lemon.  The amount of mass these computer fans have to throw around is relatively low which means less stress on those moving parts versus a larger fan.  And there are larger fans that have been around since the the 1920's. They don't make em' like they used to.

I've always run fans at 100%. Never had a failure on over 20 various cards in 5xxx, 6xxx, 7xxx, R series. However my anecdotal experiences are statistically irrelevant, its clear that certain products have QA issues and fail easily (MSI R-series non-reference coolers for example).