Topic: Powercolor 7870 LE (Tahiti) - NEED HELP! (Read 14093 times)

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.

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.

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.

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.

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

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

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 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 ?

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 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

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 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  

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

Any concurrency over 8192 crashes

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.

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

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.

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

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.

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.

PWCHD7870

that code should take $20 off for the Newegg card

cheers