'invalid nonce - HW error" message while LTC mining.

[de704]

I'm new to mining. Is it normal to see a "invalid nonce - HW error" msg while mining?

Thanks

[BitcoinBarrel]

Not really. Is it happening over and over or every once in awhile? Try lowering your intensity.

[de704]

That worked but now my hash rates are way lower than I should be getting. 

[BitcoinBarrel]

What miner are you using?

[redtwitz]

It's hard to give advice without knowing what hardware you're using and how your miner is set up.

Lowering thread concurrency may allow you to increase intensity without HW errors.

[de704]

I think it's because I was using a wireless card after switching to Ethernet cable I'm getting less errors.

BTW 2x 7970

[sublime5447]

your config file is no good change your settings. to much intensity or thread concurrency or gpu engine or memclock

[de704]

um I'm new.

I just copied what was written down can you give me an example of how to make those changes?

[krusin]

need more info, what cards specifically are you using and what miner. Post you config file too if you have one.
Help us help you.

[ncr1pt0r]

getting good advice here but best to ask this on the mining board.

[Sondey10mg]

WINDOWS: Open cmd prompt and type
Code:
setx GPU_MAX_ALLOC_PERCENT 100

[de704]

I found this answer.

The reason this is crucial is that too high an intensity can actually be disastrous with scrypt because it CAN run out of ram. High intensities start writing over the same ram and it is highly dependent on the GPU, but they can start actually DECREASING your hashrate, or even worse, start producing garbage with HW errors skyrocketing. Note that if you do NOT specify an intensity, cgminer uses dynamic mode which is designed to minimise the harm to a running desktop and performance WILL be poor. The lower limit to intensity with scrypt is usually 8 and cgminer will prevent it going too low.

Source: http://bitcoin.stackexchange.com/questions/11514/cgminer-litecoin-mining-generates-invalid-nonce-errors

To me this answer is kinda crazy because I am running 2 7970 with 6Gig NVRam Yes I know they are a waste but the explanation that they are running out of ram kinda makes me laugh.

[de704]

WINDOWS: Open cmd prompt and type
Code:
setx GPU_MAX_ALLOC_PERCENT 100

What does this do??

[TheSpiral]

WINDOWS: Open cmd prompt and type
Code:
setx GPU_MAX_ALLOC_PERCENT 100

What does this do??

Increases the amount for --thread-concurrency you can use.

[crazy_rabbit]

I found this answer.

The reason this is crucial is that too high an intensity can actually be disastrous with scrypt because it CAN run out of ram. High intensities start writing over the same ram and it is highly dependent on the GPU, but they can start actually DECREASING your hashrate, or even worse, start producing garbage with HW errors skyrocketing. Note that if you do NOT specify an intensity, cgminer uses dynamic mode which is designed to minimise the harm to a running desktop and performance WILL be poor. The lower limit to intensity with scrypt is usually 8 and cgminer will prevent it going too low.

Source: http://bitcoin.stackexchange.com/questions/11514/cgminer-litecoin-mining-generates-invalid-nonce-errors

To me this answer is kinda crazy because I am running 2 7970 with 6Gig NVRam Yes I know they are a waste but the explanation that they are running out of ram kinda makes me laugh.

Litecoin was designed to be specifically memory intensive. Change your config settings, experiment. You're probably running out of (yes even 6 gigs) memory. 

[FiiNALiZE]

I found this answer.

The reason this is crucial is that too high an intensity can actually be disastrous with scrypt because it CAN run out of ram. High intensities start writing over the same ram and it is highly dependent on the GPU, but they can start actually DECREASING your hashrate, or even worse, start producing garbage with HW errors skyrocketing. Note that if you do NOT specify an intensity, cgminer uses dynamic mode which is designed to minimise the harm to a running desktop and performance WILL be poor. The lower limit to intensity with scrypt is usually 8 and cgminer will prevent it going too low.

Source: http://bitcoin.stackexchange.com/questions/11514/cgminer-litecoin-mining-generates-invalid-nonce-errors

To me this answer is kinda crazy because I am running 2 7970 with 6Gig NVRam Yes I know they are a waste but the explanation that they are running out of ram kinda makes me laugh.

Litecoin was designed to be specifically memory intensive. Change your config settings, experiment. You're probably running out of (yes even 6 gigs) memory.  

+1

Experimenting is honestly your best option.

Every card is different. Change your memclock, core clock, intensity, etc. until you find a sweet spot.

[de704]

Ok, I think I'm figuring it out  ...

2x Saphire 7970 w/6gig ram  = 1264 KH/s & I think I can get to 1500 KH/s

This article is the holy grail for 7970's in LTC mining
https://github.com/ckolivas/cgminer/blob/master/SCRYPT-README

I googled "invalid nonce - HW error". googles my friend 

[sublime5447]

I am going to tell you how to fix it. I just fixed it on a machine that i rebuilt. I had this happen before but was able to change the config and get around it. This last machine no matter the config it would throw hardware errors and nouce errors. I could only run the card at 12 or 13 anything more would give errors and I couldn't raise the thread concurrency.

So the fixes I have seen involve running different versions of CCC (CatalystControlCenter) and cgminer. That may work I never got it to, adding RAM to the board, I know for a fact that shit doesnt matter or work. i run 5 cards off 2 sticks of RAM with no problem and I added more with no difference. The other fix is re-installing the drivers or the OS... that may be necessary if you are unsure if you have good drivers, if the ccc doesnt open or gives an error or if cgminer stops working, and the last fix I have seen is changing the code in cgminer.

But what worked for me was this.

We put SETX GPU_MAX_ALLOC_PERCENT 100 in the COMMAND PROMPT not in the configuration file... after I did that it allowed me to raise the thread concurrency.... after I could do that I could raise the intensity. Hell YA! that was a real pain in the ass to fix. I would say 20 hours of being pissed off to figure that out. I dont think this is an issue for other cards but have had the problem with 7950 and 7970... pain in the dick.