Topic: Looking for 2nd opinions (Read 1580 times)

A mining rig has mulitple temperatures throughout it's going to cause "fog" near the exhaust and condensation on it's cooler components. but feel free to test this and report back with video

Why do people always get this shit backwards? If you place something cold in a warm/hot environment, the air near the cold thing gets supersaturated with water vapor and condenses on the surface. If you place something hot in a cold environment, the air near the hot thing will accept a much larger amount of water vapor compared to the environment and will NEVER condense. The worst you'll see in this setup is fog in the air.

that's going to have a tendancy to cause condensation and other nasty things

has anyone tried running rigs inside a walk in freezer?

some inspiration for your open air setup joint, one of the rigs in there is a 1x5870 it's running at 55-60 *c

Thanks for the input.

The voltage is strange on the 6970s -- I can't adjust voltage on any of the cards, but one is at 1.150 and the other two are at 1.175.  Go figure.

They are all locked in the case but I'm likely going to open the case and direct a desktop fan towards it.

All by itself, the clock does not influence the longevity in any way.

However, power consumption and dissipation rise linearly along with clock speed and those two factors are the chip killers when the microscopically small traces inside the chip "burn up" (actually, it's electromigration that kills them - a process where electric current displaces molecules of the conductor it's running through).

Load (heat and current) also leads to degradation of transistors inside the chip to the point where they become unstable at speeds they used to run at without any issues. If your card suddenly starts crashing where it used to run stably for months dropping the clocks is the only solution.

95% fan speed (or even 85%) is something you should worry about. When manufacturers cut corners, fan quality goes first.

Chances are that when purchasing inexpensive 10$ case fans you are getting much higher quality devices than the ones mounted on your 300$ card...

70..79°C is not a bad temperature range for a battery of overclocked 6970s locked in a PC case. If it's an open rig, try increasing the distance between cards or pointing more airflow directly at them.

It's a bloody damned shame that your manufturer seems to have cheaped out on the VRMs - undervolting should drop the temperatures just enough for you to be able to reduce the fan speed to sane levels.

TL;DR:
(1) && (2) No clock - all by itself - is too high provided the card is stable. 79°C isn't exactly low but it'll do.
(3) Yes.
(4) Independent of current and temperature, no.

I'm looking for some second opinions about the longevity of my setup.  

I have 3x6970 in one rig and another 1x5870 hashing away.

Current settings using cgminer on the 6970s are:
950/685 (mem is lowest I can get without flashing BIOS)
V=1.175 (can't adjust in cgminer or afterburner)
I = 9
Fan = 85% on 2 cards, 95% on the hottest card
Temp = 79C on Hottest card, 70C on coolest.
Powertune = 10
@ 425 m/hash each


Current settings using cgminer on the 5870 are:
980/350
V = 1.130
I=9
Fan = 40%
Temp = 53C
Powertune = 0 (Can't adjust for this card on cgminer)
@405 m/hash

My questions:
1)  Is 950 core or 79C too much/high for the 6970?
2)  Is 980 core (stock 850) too high for the 5870?
3)  Are the fan speeds on the 6970s an issue?  They are HIS 6970s.
4)  Most importantly, does an increased core clock affect the longevity of a card independent of temperature and voltage?  I assume 53C and 40% fan to be no concern, but does a +130mhz overclock present a problem for longevity in and of itself?


I'd really not like my card warranties to be voided because I leave some burns somewhere or something.