AMD 7970 LTC Mining, CGminer, Crash on LTC, not on BTC

[Schrankwand]

Hi everyone.

I have a new Gigabyte 7970, the big version with 1100mhz core clock.

Card gets up to 730mh/s with cgminer on Bitcoin with 1180/1030 with temperatures above 90°, probably enough to make an omelette. Core voltage is unfortunately locked at 1.256v.

I have used this setting before for LTC on cgminer:

cgminer --scrypt -o http://eu-pool-d.give-me-ltc.com:80 -u Schrankwand.1 -p x --shaders 2048 --thread-concurrency 8192 -I 13 -g 2 -w 256

I have MSI Afterburner running and set core clock to 1100 and increased Memclock slightly to 1600 stable. But that seems to be it. I get about 600kh/s and it does crash after some minutes.
I believe this card should be able to run at FAR higher ratings than this, especially considering that it is voltage locked at 1.256.

Problem description: While card runs stable at high hash rate and above 90° core temp at bitcoin, it near crashes on LTC within 5 minutes, showing complete screens in blocks, sometimes in blue, sometimes in white. Stripes, vertical, actually. On LTC it never even reaches high temp, maximum is 70° before crash.

Any help? Something I am totally fucking up here?

Drivers version is 8.982-120727a-144338C-Rage 6.

System is running on windows 8.

[frojoe]

From what I understand LTC is more memory intensive and BTC mining. When I OC my memory on my 7970 and they are watercooler my VRMs I say get to hot for my liking. Iv seen them in the 70c range or close to it. Sounds to me vrms or memory are overheating. I used HWinfo64 to get those stats.

[Jude Austin]

I can help you.

If you would like I can set it up for you.

PM me your TeamViewer information and we will get started.

[Schrankwand]

Update on this:

Card runs stable at 600kh/s. Can get it up to 640, but then it starts to become a 95° toaster.

Problems so far: Settings are all correct, memory overclock doesnt work right over 1600mhz. So now im at 1050/1600 at 1.256v. Thinking about getting another card.

[previse]

I have a gigabyte 7970 as well and i get 700-715 kh/s @ 70 Deg C

[Schrankwand]

I have a gigabyte 7970 as well and i get 700-715 kh/s @ 70 Deg C

Probably better housing than mine. I am using it in a way that might not be recommended, leading to limited air circulation.

However the card crashes before it even gets hot if I overclock it... what did you do to get there?

[logicus]

For 7970(cgminer) try 900 MHz core and 1580 MHz memory: thread_concurrency 22392 (~700 kh/s can be obtained with a core/memory ratio of 0.57) or 8192 (-g 2 -w 256 -I 13)

[Schrankwand]

For 7970(cgminer) try 900 MHz core and 1580 MHz memory: thread_concurrency 22392 (~700 kh/s can be obtained with a core/memory ratio of 0.57) or 8192 (-g 2 -w 256 -I 13)

I must have something completely different than you guys here. Dunno about this card, seems to be somehow deviant.

I can mine LTC with 1150/1500 at 620kh/s core, at your settings it gives me 490kh/s at 8192 and completely crashes on 22392.

[crazyates]

For 7970(cgminer) try 900 MHz core and 1580 MHz memory: thread_concurrency 22392 (~700 kh/s can be obtained with a core/memory ratio of 0.57) or 8192 (-g 2 -w 256 -I 13)

I must have something completely different than you guys here. Dunno about this card, seems to be somehow deviant.

I can mine LTC with 1150/1500 at 620kh/s core, at your settings it gives me 490kh/s at 8192 and completely crashes on 22392.

LTC is a bitch. The same settings that work one place don't work in another.

[Schrankwand]

For 7970(cgminer) try 900 MHz core and 1580 MHz memory: thread_concurrency 22392 (~700 kh/s can be obtained with a core/memory ratio of 0.57) or 8192 (-g 2 -w 256 -I 13)

I must have something completely different than you guys here. Dunno about this card, seems to be somehow deviant.

I can mine LTC with 1150/1500 at 620kh/s core, at your settings it gives me 490kh/s at 8192 and completely crashes on 22392.

LTC is a bitch. The same settings that work one place don't work in another.

What pisses me off with this card is that its memory settings only go to 1600mhz.

I mean, the core is a normal one, that is already overclcoked from 925 to 1100. I have put this in a burn in test yesterday and it survived 15 minutes of furmark on 1210. But put memory to 1650 -- boom.

[Jude Austin]

When your memory is at 1600, put your engine at 1000.

Then move the engine speed up or down in 5Mhz increments and see if that helps.

Just takes a lot of tweaking.

Make sure you are using 2 threads and 13 intensity.

Also be sure to delete the .bin files in the cgminer directory before running a new configuration.

They should say Tahiti in them somewhere.

Just put memory as high as it can go and start at say 950 engine speed and work your way up.

You will see the hash rate increase and stabilize once you hit the sweet spot.

You'll get it.

[Schrankwand]

When your memory is at 1600, put your engine at 1000.

Then move the engine speed up or down in 5Mhz increments and see if that helps.

Just takes a lot of tweaking.

Funny thing: I did that. Here is my results from the last 30 minutes:


System now running at 1175/1600, stable. Gets me 635. 1180 to 1185 crashes.

This is a seemingly ridiculous setting, right?

Also be sure to delete the .bin files in the cgminer directory before running a new configuration.

They should say Tahiti in them somewhere.

This, I actually didn't. I noticed them piling up, unsure if they do anything lying around there...

[crazyates]

For 7970(cgminer) try 900 MHz core and 1580 MHz memory: thread_concurrency 22392 (~700 kh/s can be obtained with a core/memory ratio of 0.57) or 8192 (-g 2 -w 256 -I 13)

I must have something completely different than you guys here. Dunno about this card, seems to be somehow deviant.

I can mine LTC with 1150/1500 at 620kh/s core, at your settings it gives me 490kh/s at 8192 and completely crashes on 22392.

LTC is a bitch. The same settings that work one place don't work in another.

What pisses me off with this card is that its memory settings only go to 1600mhz.

I mean, the core is a normal one, that is already overclcoked from 925 to 1100. I have put this in a burn in test yesterday and it survived 15 minutes of furmark on 1210. But put memory to 1650 -- boom.

System now running at 1175/1600, stable. Gets me 635. 1180 to 1185 crashes.

I can OC my mem to 1825MHz, and I can't get near 635KH/s. I've tried 1 thread and 2. I've tried different thread concurrencies, ranging from 8192, 10240, 20480, 22528, or 24000. I've increased the hashrate in 5Mhz increments from 900 all the way too 1180, and all it ever does is increase 2-3KH/s every bump - it never evens jumps any higher. My best hashrates only come at -I 13, anything higher or lower than that and it drops. It's so annoying.

[-ck]

Ironically the overclock 7970 GPUs don't mine LTC as well as the stock reference design. It's (now) a well known issue.

[crazyates]

Ironically the overclock 7970 GPUs don't mine LTC as well as the stock reference design. It's (now) a well known issue.

I wonder why that is? Seems odd.

[-ck]

Ironically the overclock 7970 GPUs don't mine LTC as well as the stock reference design. It's (now) a well known issue.

I wonder why that is? Seems odd.

See here:
https://bitcointalk.org/index.php?topic=174036.0

I'm guessing the non-reference cards use a chipset design/layout/timing that simply does not work as well for this workload thanks to some exquisitely timing sensitive harmonics.

[Schrankwand]

Ironically the overclock 7970 GPUs don't mine LTC as well as the stock reference design. It's (now) a well known issue.

Well, that is what you get for being gaming oriented. I just got myself the one with lots of reviews, ridiculous core clock and thought "to hell with it."

So, in essence you are telling me i could have saved around 100 euros, got myself a stock card, used less electricity and got better results

Irony. But since I AM a gamer, it is okay. Annoying, but okay.

[-ck]

Ironically the overclock 7970 GPUs don't mine LTC as well as the stock reference design. It's (now) a well known issue.

Well, that is what you get for being gaming oriented. I just got myself the one with lots of reviews, ridiculous core clock and thought "to hell with it."

So, in essence you are telling me i could have saved around 100 euros, got myself a stock card, used less electricity and got better results

Irony. But since I AM a gamer, it is okay. Annoying, but okay.

Well not all is lost. The tuning on those is just very different and is better with lower TCs, intensity and more gpu threads, but the hashrates are not better.

[crazyates]

See here:
https://bitcointalk.org/index.php?topic=174036.0

Ah gotcha. I hadn't read that link, as I never visit the alt-coin sections. That's crazy, tho.

Irony. But since I AM a gamer, it is okay. Annoying, but okay.

Pretty much the same here. I love gaming on this card, and the crazy OC and decent temps makes this awesome for BTC mining. I'm not a huge fan of LTC anyways, but I just wanted to see how far I could push it.

[Schrankwand]

Ironically the overclock 7970 GPUs don't mine LTC as well as the stock reference design. It's (now) a well known issue.

Well, that is what you get for being gaming oriented. I just got myself the one with lots of reviews, ridiculous core clock and thought "to hell with it."

So, in essence you are telling me i could have saved around 100 euros, got myself a stock card, used less electricity and got better results

Irony. But since I AM a gamer, it is okay. Annoying, but okay.

Well not all is lost. The tuning on those is just very different and is better with lower TCs, intensity and more gpu threads, but the hashrates are not better.

Hi everyone,


I was pretty successful with the work I did and the card runs fine. I did some more modifications to my case, which keeps it cool enough.

So, apart from that, I notice stales coming up. Usually, these appear at the single moment when a new block is detected on the litecoin network. Is there any way around this? I had 3-4% before, but one day I had 1500 shares and ~120 stales, so that hurt a little bit.

Cgminer then says "Job not found"