Bitcoin Forum

Hello,

Up until a few months ago, I used to mine bitcoin using Guiminer and the 50btc pool. (Using my wimpy 6870)

I recently tried to mine bitcoin again (Moved to Litecoin about a month ago) and I could not get it to work with guiminer.

I kept receiving RPC errors.

Since then, I have backed up my wallet, uninstalled and deleted all folder related to bitcoin qt and guiminer, and then installed the newest versions of each. (0.8.1 and 20121203)

Now after this I am receiving "Verification Failed, Check Hardware!" errors.


Am I missing a part of the setup? I do not remember having to do anything else other than download guiminer and start mining before.
(I know that I will not get much out of mining with my 6870, but I would like the option to switch between bitcoin and litecoin based on the profitability)

Here of some screenshots of my stuff in case someone can see the issue.
http://imageshack.us/a/img404/2333/gui1k.jpg
http://imageshack.us/a/img13/2481/gui2j.jpg
http://imageshack.us/a/img822/421/gpuy.jpg
http://imageshack.us/a/img593/2157/bitcoin.jpg
http://imageshack.us/a/img844/6424/poclmnini.jpg



Thanks in advance.

Anyone know what the issue is?
(Besides noob operator)
 ???

possible reasons:
too much overclocking
defective hardware

Thanks for the reply.

I will try it without the OC and see what happens.

I do not think that the hardware is bad. (I have used it before, with the same OC, and everything worked)

I am currently using it for Litecoin mining/gaming and have not run into any issues with it.
Only when I try to mine bitcoins do I get these errors.

Darn. :(

Still does not work.

I reset the OC back to factory and I still receive the check hardware error.

I don't see how it could be faulty hardware since this card is currently mining LTC at 330 k/hs with the full OC.

Are there any other suggestions from the bitcoin gurus on what I can do to fix this error? 
Thanks in advance.

http://imageshack.us/a/img443/4665/againh.jpg

Bump.   Please assist.

Added 2 more 6870's.  I have 3 6870's mining litecoin at ~900 kh/s but still can't mine bitcoin. :(

This error message comes from the miner kernel (the software that runs on your video card) returning a block hash that upon a double-check before sending is not a valid block hash. If it is happening all the time, there is a compatibility problem with the different versions of software/driver/hardware that you have installed.

If this is a mine-only machine using HD 5xxx-HD6xxx hardware, I would recommend using the ATI driver package 11.11 with it's included OpenCL (you must first manually remove the current driver and remove some files manually (https://bitcointalk.org/index.php?topic=63616.msg745198#msg745198) that aren't removed by the install). Then CGMiner or Phoenix software instead of GUIMiner, plus underclock your GPU memory to 300MHz.

I'm having the exact same issue with 13.4 on my HD5870.

Well which drivers do work? I don't use my mining PC to just mine, I need the latest drivers for other work.

I seem to just have gotten the same thing.

I had a GTX660 (desktop card only), 6870, 6450, 7750 going fine for 3 weeks. I had 13.4 and SDK 2.5 installed.
Shut it down to try out a 4850x2 for mining. Took out all other cards.
Much hassle figuring out I needed 12.4 drivers. Used Driver Sweeper to remove all AMD stuff.
Never got the 4850x2 to mine. (Crashed all my mining software). Took out 4850x2. (reading it sucked anyway)

Reinstalled GTX660, 7750, 6450. Reinstalled 13.4 and SDK 2.5
7750 __works__, 6450 was producing errors.
Took out 7750.

Put in 6870, now producing errors

Even the GTX660 says 'cannot create CUDA context' when i try to mine with it. (it did 70Mhash the week before just to test)

Took out 6450, reseated 6870, still errors.

That's where I am.

BFGminer, CGminer and Phoenix all barf at my cards, except the 7750.

Any ideas?

What drivers/sdk are you using?

Hey guys,

I've posted about this problem at https://bitcointalk.org/index.php?topic=227918. This fix is mostly limited to CGMiner/BFGMiner but the problem is the same, so the solution should be similar.

Good luck, and let me know if you need more help!

Note: my 'fix' removes a switch and as such may break mining with other cards (or reduce performance!!)

https://bitcointalk.org/index.php?topic=221041.0

Whichever one of you that posted this. it works.

Using GUIminer, locate poclbm.cl and simply replace

#ifdef BFI_INT
   #define Ch(x, y, z) amd_bytealign(x, y, z)
#else 
   #define Ch(x, y, z) bitselect(z, y, x)
#endif

with

#define Ch(x, y, z) bitselect(z, y, x)

where is poclbm.cl located? i knwo its old topic but i need to find it on windows.

it should be in the extracted file of guiminer so depends where you extracted it to after download

why not use bfgminer? guiminer is dead with flaky support and hacked in stuff