Bitcoin Forum

Ok guys. I'm setting up a rig for a buddy I work with and I'm about to throw the damn Powercolor cards out the window.

Specs:
A6-5300
Asrock extreme 6
4gb of ddr3
1000 watt OCZ gold
and 2 or 3 Powercolor 7870 tahitis

Problem:

No matter what settings I use I cannot get the cards to mine over 330kh/s. The cards are voltage locked so I can't adjust that. Stock clocks are 925 core and 1500 mem.

example cgminer .bat:

cgminer --scrypt -o http://litecoinpool.org:9332 -u x -p x --lookup-gap 2 --thread-concurrency 8192 -g 2 -I 13 -w 256

This is stable and gets me 330kh/s any intensities over 13 cause massive hardware errors

if I try:

cgminer --scrypt -o http://litecoinpool.org:9332 -u x -p x --lookup-gap 2 --thread-concurrency 16384 -g 1 -I 13 -w 256

cgminer won't start


basically nothing I try will get these cards to run... To boot, they artifact if turned up to the first setting listed above.


I've tried them on my test bench and get the same results. I tried reaper and got shutdowns, false starts at settings that would give good kh/s.


Should I just return all these cards? ( I have 4 of them)


Thanks for any help you can give.

In afterburner, set core to 950 MHz and memory to 1555 MHz

use reaper and this litecoin.conf


Tell me what you get

Try also aggression 18

If you search the cgminer thread there is a setting you can enter in a CMD window.  setx GPU_MAX_ALLOC_PERCENT_100 or something similar.  Check there for the exact setting, you dont want to use something else.

That will fix the CGMiner not starting with higher thread concurrencys if you are using 11.3.

i'd return them...that 7970 powercolor i had...sent it to rma and the card they gave me back worked for a whole 4 days mining btc before it quit...just sent it out today for another rma...powercolor is just shit imho...hopefully 3rd times a charm with this company...good luck to you

Since its a tahiti, try running 950/100 thread concurencies 24000 - these tahiti chis really dont have a pattern for ltc, every card is different

Thanks for the suggestions guys. Will try when I get home and update.

Are you running 4 cards all together and each get 330Kh/s

I might be wrong, but if you are mining LTC with 4G of RAM and 4 7870 cards, it's not a good combination.

I personally use 3 powercolor 7950, the max -I is 13 higher than this will product massive HW......so I guess you don't need to bother this parameter

you don't need --thread-concurrency 8192, my cards all mining at 510Kh/s just fine without it.

so I can only conclude that increase your system RAM to 6 or 8G, and see if hashrate increases

No go on changing any options. Couldnt get cgminer to start with: setx GPU_MAX_ALLOC_PERCENT_100

Reaper crashes with intensity over 13 or so as well.

Deleting all options except -i 13 gave me about 300kh/s

Interestingly if I downclocked the core to 725mhz it increased the hash rate to 315kh/s... Downclocking memory had detrimental effect after hitting below 1400mhz


I initially tested 2 cards together on 1 board with 4gb of ram. (I run 3 5970s on the same type of board with only 4gb and get standard hash rates). I then tested only 1 card on the 4gb board. Then tested another card on a different board with 2gb... Got the same results.

I can't flash bios as RBE doesn't recognize any 7800 series bios... ATIwinflash won't let me flash either. I believe the bios is locked.... I'm just about through messing with these mother fuckers...

Gonna enjoy having to send them back to newegg. Hopefully they don't charge me a restocking fee.


Any other suggestions would be appreciated but at this point I don't think there is much else to try.

Should also mention I'm running 13.1 drivers... gonnna try the 13.3 beta drivers

interesting, did you try to change -w to 128 or 64? and try to keep the core/memory ratio to about 0.7

This is the reason why I gave up litcoin mining couple months back.  Couldn't get my 7000 series cards anywhere near what some people reported, or close enough to what I get with bitcoin mining (550Mh/s ~ 550Kh/s).

I've tried 128...

I have a 7970 diamond mining at stock clocks and 520kh/s.... Its not a 7000 series problem... This is just a POS powercolor problem :) Lol.

Anyways, I flashed to the MYST bios and no luck. I'm gonna try and flash to a sapphire XT bios. If that doesn't work I'm gonna just chalk it up to Powercolor buying some of the most crappily binned tahiti cores it could find and then shipping the finished product to unsuspecting customers.

On a possibly related note, I did ran the GPU-z ASIC quality test on one of the cards and it got a 59%... Maybe its the high stock clock (925 core and 1500 mem)...

Try 725 MHz and 1500 MHz RAM, intensity 14, 16, and 18

There may just not be enough memory bandwidth for that many shaders

Nope, nope, and nope... Massive hardware errors when any intensity over 13 is tried no matter core or memory settings.

All my GPU's mine perfectly with a slight core OC, under clocked Memory and undervolted. Upping the Memory speed doesn't do anything but raise heat levels for me.
7970,6950,5850 and 6870's. I use cgminer.

 KWH we are talking about litecoin and scrypt here, not bitcoin.

LTC is what I mine. Assume much?

Oh well... I have 3 of them mining away on a board for right this second. They are going back to Newegg on monday though. Wonder if they'll give me shit since I haven't game tested them?

I've yet to have an issue with returns to NE, always a first though. Good luck!

good choice

Could you post a link to the specific cards that were purchased?

^ That is the card. Please update on your experience with it.

PWCHD7870

that code should take $20 off for the Newegg card

cheers

I must have really bad timing because I ordered 4x of these on Thursday: http://www.newegg.com/Product/Product.aspx?Item=N82E16814131487

Despite paying for overnight shipping I received every part of my order, but the motherboard I needed to set it all up. That motherboard now seems like it is going to show up Monday. In doing some extremely basic testing with all of my mining boards (ASRock 970 extreme4(s)) I had to update the bios for the board to even post with the card. Then, on an already setup windows 7 / 12.8 install the cards kept showng up as standard VGA adapters. While uninstalling and reinstalling 12.8 the install would work fine, but come up with a blank warning at the end and the card would stay as a standard VGA adapter in device manager. I then removed one 7970 from my main computer ASRock OC Formula, it posted fine, and Windows automatically identified the card as a 78xx. I'm hoping when I get the other 970 Extreme4 that it will work just like my OC Formula and that it was just an install / driver conflict. I'm guessing I'll get to play with them more on Monday.


Where did you find that code? It took $31.20 off of one card for me. The cards I ordered Thursday ended up being $244.99 + shipping where as the myst card ends up being $208.79. Pretty much bullshit.

Update on this:

Hardware:
3/4 Powercolor 7870 EZ Edition (1 more to be installed when the risers I ordered shows up)
ASRock 970 Extreme4
Sempron 145
4 GB Ram
Sparkle 1200 Gold PSU
USPS Priority Flat Rate Case   ;)

Software:
CGMiner 2.11.3
Windows 7 Ultimate x64
Catalyst 13.1 with included SDK
MSI Afterburner 3.0.0 Beta 8
http://www.guru3d.com/files_details/msi_afterburner_beta_download.html

Catalyst 12.8 absolutely refused to recognize the cards at all. I finally got fed up with trying to get it to work, downloaded, installed 13.1, and the cards were instantly detected. I tried Afterburner 2.2.5 like I have on my other rigs, but it wouldn't allow me voltage control. Googled for 7870 tahiti voltage control and found a link about the new Afterburner 3.0.0 Beta 8 which allows voltage control for 7870 tahiti editions. Installed that, went into settings, and setup unofficial overclocking (much easier than older versions). That allows memory underclocking and full voltage control.

Results:
2 GPUs Installed
975 e / 170 m / 1.081 v
430 mh/s / card

Voltage was a little weird because CGMiner reported 1.256, Afterburner 1.081, and GPU z 1.030.

3 GPUs Installed
975 e / 170 m / 1.100 v
412 mh/s / card

Temperature:
Space the cards are in: 81.5 F
GPU 1 Riser: Roughly 30% fan 72 C
GPU 2 First 16x slot: Roughly 60% fan 73 C
GPU 3 Last 16x slot: Roughly 30% fan 72 C

I had to add a 120mm fan on top of GPUs 2 and 3 to help keep them cool. Before I dropped the voltage on all of the cards I couldn't keep GPU 2 cool at all. The fan would run up to 100% and I would have to shut the machine down as the temperature kept climbing. After dropping the voltage the temp dropped a ton, but the card still has some issues without the fan on top of it. I'm going to try putting it on a riser as well to get it away from GPU 3 or mix these in with my 7970 rigs. I play with the core clock on them then. After spending so much time on it today I was kind of just happy to have it hashing and wanted to leave it alone.

I've noticed this with my other rigs, but adding cards drops the hash rate of each individual card. I don't know what causes it, but if anyone has an idea let me know. I've had varying results in adding a 4th card to some of my rigs, but I'll post more results when the risers I ordered shows up.

What settings are you using? I can't get them anywhere near that with litecoin or bitcoin.

Config for two of them:

"intensity" : "9,9",
"vectors" : "1,1",
"worksize" : "64,64",
"kernel" : "poclbm,poclbm",
"lookup-gap" : "0,0",
"thread-concurrency" : "0,0",
"shaders" : "0,0",
"gpu-engine" : "0-0,0-0",
"gpu-fan" : "0-85,0-85",
"gpu-memclock" : "0,0",
"gpu-memdiff" : "0,0",
"gpu-powertune" : "0,0",
"gpu-vddc" : "0.000,0.000",
"temp-cutoff" : "95,95",
"temp-overheat" : "85,85",
"temp-target" : "75,75",
"api-port" : "4028",
"auto-fan" : true,
"expiry" : "120",
"gpu-dyninterval" : "7",
"gpu-platform" : "0",
"gpu-threads" : "2",
"log" : "5",
"queue" : "1",
"scan-time" : "60",
"temp-hysteresis" : "3",
"shares" : "0",
"kernel-path" : "/usr/local/bin"

EDIT: I should have read this better because I am mining BTC. I can give them a LTC test if you shoot me an idea on how to set it up.

ok... got your settings working. Thanks by the way. Unfortunately I don't mine bitcoins anymore. Tell you what, if you can get similar results mining litcoins (around 400 or so kh/s without massive hardware errors) I will send you 10ltc.


And if the recent movement keeps up that will be a substantial ammount of money! lol ;)

My reaper settings for the 7870 LE (Tahiti XT) are:

GPU 855
Mem: 1500

worksize 256
vectors 1
aggression 20
threads_per_gpu 1
sharethreads 24
lookup_gap 2
gpu_thread_concurrency 24000

Sometimes I use 16384 instead of 24000, it usually depends on the pool. I get an easy 400-420 kh/s with these settings.

Any concurrency over 8192 crashes

I got my HD7870 MYST Edition from Newegg today. It took some work, but I finally consistently over 400kH/s using reaper with this card without crashes or high number of invalids.

Using AMD Overdrive section of Catalyst 13.3beta - Set GPU clock to 855MHz, Memory 1500MHz. There may be better values. This worked for my setup.

I also had to edit a couple lines in reaper.conf

Finally, here is my litecoin.conf

I get a steady hash rates >400kH/s. You can increase the aggression to 19 or so to increase the hash rate slightly. For me any other cpu_thread_concurrency value seemed to cause either hardware errors or invalids.

I got similar has rates with cgminer by setting using the following command line arguments, but it wasn't communicating with the pool correctly for some reason. For now, I am sticking with reaper.

If this works for you, great. Feel free to send that 10ltc bounty my way  ;D

If anybody finds a better configuration. I'd love to see it.

I'm also having issues with this card. Shame, it mines BTC very well.. The best I have eeked out was 390Khs underclocked to 855 with thread concurrency of 24000 :\

I appreciate all of the responses.


^^I tried the settings you suggested in cgminer and it just crashed... I tried adding the GPU max alloc thing and it didn't help.


I ended up just selling these to someone that wants to mine bitcoin with them. ^It is a pitty but they do get 450mh/s or so on bitcoin so they aren't worthless.... And who knows maybe they'll be fixed in a driver update?

Thanks,
Andrew

took me a few weeks to figure it out.   I downclocked memory all the way, reduced voltage to -8% to -11% range and upped gpu clock to 1195-1205mhz, then in guiminer i used worksize 256   "-v -w 256"   i get 500+ mh/s now and card is at 73-75c versus 76-78c

I gave up mining LTC on my Pitcairn 7870 over a month ago. The best I could do was 310 khash/s with HW errors. And tbh, I'm feelin any motivation to try with my Sapphire 7870xt. lol

Why some GCN chips seem to run ok and others don't is anyone's guess.

Has anyone tried comparing their mobo bios versions and/or gpu memory make/model and/or system memory timings configs ?

Sorry for the necro but I am experiencing the same issues with my tahiti le ez.
I have it kicking ass at btc at 550 mhash but I cant get it about 240 khash with ltc or anything scrypt.
Not sure what to try from here as there are several suggestions, some I already tried.
Setting the TC above 8192 doesn't work.

13.5b2, SDK 2.7(i think) running on W8.

I'll try again but this time I'll start with the 12.8 drivers.

Many tips here..
https://bitcointalk.org/index.php?topic=117221.0;topicseen
https://bitcointalk.org/index.php?topic=208857.0;topicseen

Odd I've pulled 400KH/s on the standard 7870

850 core, 1500 mem, .981v

Reaper 16384 threads, 1, 1, worksize 256, intensity 18 ~400kh/s

I have 2 Tahiti myst cards in one machine and they both work fine with these settings.

I know the 7870 Tahiti LE mines BTC very well.  I get 500+ mhash/sec each card at -20% voltage.   I also do not understand that your cards are voltage locked; two of mine are not.


LTC...who knows?   It should do ~400-500khash/sec easy though.

If you want help I can remote in via teamviewer; PM me.


These cards if setup right should break even in 3 months mining BTC.

The highest I've been able to get LE EZ is 380 khash. I was hoping to atleast get 420 khash or there abouts. Any less and I'm better off just mining BTC. I thought if I put my 6870 back in along with it I could use that for ltc while mining btc with the EZ, now I cant get either to mine consistantly, but I guess thats a whole 'nother kettle of fish. Might try switching to Ubuntu and see if I have better luck.

This was extremely useful for me. Other than M=1555 which was too high (1375 worked great for my Powercolor), everything else was used in cgminer 3.7.2 to increase hash by over 15%. Thanks!

BTW, my GPU  is not even Tahiti, but Pitcairn, yet the parameters hold well.