Bitcoin Forum

Hello-

I recently popped my two 5830's in my box.

I did not crossfire them, and when i begin to mine they both put out around 255.5 M/Hs

if I wait a couple of seconds the second card will drop down to 150 M/H's

I am using windows 7 64 bit
GuiMiner 5/21/11


any help?

Try with poclbm first, run one on the first GPU, wait 10 minutes and and then run another one on the second GPU, wait a few and then see if it drops, try playing with -f and -w.

are you sure you are not running more mining instances on a single card? I do that sometimes.

I have tried the first option of waiting, starting another s3ession of the miner, i am getting the same results

pcie x8 v x16 matter at all?

what flags would you suggest i try?

Thank you again.

Check your GPU temp on the troubled card.  I had a similar problem when a GPU went >90C. 

You are completely correct, I didn't even notice card was at 93c.

The fan on the card is not functioning, sigh, RMA time i suppose

Thank you for your help.

i have 2 HD5870,i'm using win 7 ultimate x86 with CCC 11.4 SDK 2.1.
but when mining,only the first HD5870 runs ???

how can i fix it ? Any guide for me   :-[
thanks

It is temperature problem mostly.
I have 2x HD5870 and second was steadily 100Mh/s under first. One 120mm fan gives me this 100MH/s, so it is definitely best coin/buck hardware :-)

seems to be a bug in linux with the graphics drivers & gnome or whatever the desktop gui is called.

Here's how it affected me:

running 4 cards. If I ran the 3 that my monitor was not plugged into, all was fine.

If I ran the "main" card, cpu would peg at 100%. The mhash rate of ALL cards would fluctuate wildly, averaging about 10-15% lower than when not running the main card.

Top would show kworker using 40%cpu, and the miners (phoenix) using up to 20%

I switched to headless ( with a /etc/init/gdm.conf that looks like exec /usr/bin/X 2>&1) and all was good.

all four cards run at a consistent rate, and cpu is about 5%


(this is actually the first time in my life I've used a linux gui! even though I've logged thousands of hours on linux servers. And I didn't use it long before ditching it...)

I have 2x 6950 in linux, if I'm on it with remote desktop or locally, the secondary card drops from 340Mhash/s -> 260Mhash/s. But if I leave the comp alone(no one logged in/no cables attached), deepbit reports ~680Mhash/s over time. And I have equal amount of done shares from both of them.

i have a 5850 and a 5830. if i run only the 5850 (device 0) i get 300 Mh/s @ 55ºC. as soon as i open the second miner for 5830 (device 1). the performance for the 5850 decreases to 260 Mh/s @ 58ºC. im sure this is not about temps...

windows xp
phoenix miner phatk kernel
cpu load 15%


when 5850 is mining alone, gpu usage stays @ 95%.
when 5850 is mining at the same time as 5830, 5850 gpu load decreases to 80% and 5830 gpu load stays @ 92%

im using the 5850 as my primary card


can you help me??

Are you sure this can't be effect of GUI using the card?  Try -f 1 or similar FPS option.

Other reasons for card slowing might be network problems (but no reason for it to affect just one card)...

Is it always the 2nd card? Even if it works alone? As last resort I would try if switching their places (PCIe slots) helps (probably not)

if i mine only with 5850 (device 0) using -k phatk DEVICE=0 PLATFORM=0 AGGRESSION=5 VECTORS BFI_INT WORKSIZE=128 -> 315 Mh/s (gpu @ 95%, temp @ 60ºC)


as soon as i start mining with 5830 (device 1) using -k phatk DEVICE=1 PLATFORM=0 AGGRESSION=6 VECTORS BFI_INT WORKSIZE=256 (so now their mining at the same time), 5850 drops to 260 Mh/s and 5830 stays at 245 Mh/s

Is the card that drops regularly the one your monitor is on? if you use the PC whilst mining the GPU will still need to be used to display the desktop, which will reduce your hash rate, especially if you start watching things on Youtube with Flash hardware acceleration enabled...

yes, the card that drops hash rates is the one the monitor is connected to. im not playing any video or anything like that

but that doesnt explain why i can get 320 Mh/s (98% gpu usage) on the primary card (display) while the other card is not being used.

EDIT:

i found what the problem was. i was using chrome with gpu acceleration. closed it and started the miners again and everything is fine now :D

hmm, hadn't thought of that, :)