hashcat Forum

Hi, what is the gpu utilization? When I run oclHashcat on my two 7970s I never get above 85%. I don't have anything else running that could use the gpus except for the x11 server that is required to initialize the cards.

Give it enough work to do otherwise they can not reach full performance.

For example:

- if you use -a 0, -a 1 or -a 6, make sure the base dictionary (left) has at least 10 mio words (per gpu).
- if you use -a 3 or -a 7, make sure your left mask keyspace > 500k entries (per gpu). for -a 3, this is the keyspace of the first 4 chars of your mask.
- make sure your modifier (right) iterates at least through a keyspace of 1k. in case if -a 0 its the number of rules, in case of -a 1 and -a 7 its the number of words in the right dictionary, in case of -a 6 its the keyspace of the right mask.

The workload modifiers are set to low.

If you dont care about screen lags, raise -n and --gpu-loops. For example -n 160 --gpu-loops 1024.

(09-03-2012, 11:23 AM)atom Wrote: [ -> ]Give it enough work to do otherwise they can not reach full performance.

For example:

- if you use -a 0, -a 1 or -a 6, make sure the base dictionary (left) has at least 10 mio words (per gpu).
- if you use -a 3 or -a 7, make sure your left mask keyspace > 500k entries (per gpu). for -a 3, this is the keyspace of the first 4 chars of your mask.
- make sure your modifier (right) iterates at least through a keyspace of 1k. in case if -a 0 its the number of rules, in case of -a 1 and -a 7 its the number of words in the right dictionary, in case of -a 6 its the keyspace of the right mask.

The workload modifiers are set to low.

If you dont care about screen lags, raise -n and --gpu-loops. For example -n 160 --gpu-loops 1024.

thanks!

I'm using hashcat lite with ?a on a single ntlm hash. I've added -n 160 --gpu-loops 1024 but that does not seem to make any difference, gpu utilization stays at 85%.

And your command line is?

@atom:: Thanks for the valuable info!

(09-03-2012, 04:11 PM)M@LIK Wrote: [ -> ]And your command line is?

Quote: I'm using hashcat lite with ?a on a single ntlm hash. I've added -n 160 --gpu-loops 1024

the above?

./oclHashcat-lite64.bin -m 1000 -1 ?a -n 160 --gpu-loops 1024

Then is using the default mask.

Please read this article to understand how masks work: https://hashcat.net/wiki/doku.php?id=mask_attack

So my mask is ?1?2?2?2?2?2?2?3?3?3 for a password of length 10.

Quote:- if you use -a 3 or -a 7, make sure your left mask keyspace > 500k entries (per gpu). for -a 3, this is the keyspace of the first 4 chars of your mask.

Since I'm using the lite version, I'm assuming it's equivalent to -a 3 of the plus version? In that case, why are the only first 4 chars are relevant? What mask do I need to get close to 90% for example?

The other thing I found interesting is that when I swapped the processor & motherboard to amd fx8150, the utilization dropped from 85% (with intel processor) to 81% on both cards. Both motherboards use PCIE2.0 16x and I didn't change the command line for hashcat after I swapped the processor + mobo.

--restore-timer=60
Also disable integrated gpu if it exist on mobo, disable-remove crossfire.

(09-04-2012, 05:34 PM)KT819GM Wrote: [ -> ]--restore-timer=60
Also disable integrated gpu if it exist on mobo, disable-remove crossfire.

--restore-timer=60 didn't make any difference. There is no integrated gpu and I'm not using crossfire