Hashcat only using ~2% of GPU?
#1
Hi! If I sound like a noobie, I apologize. It's probably because I'm a newbie. But anyways, I'm having some (I think?) troubles with Hashcat. I'm trying to use it to crack a WPA2 captured handshake password that I got with aircrack-ng using The-Distribution-Which-Does-Not-Handle-OpenCL-Well (Kali) Linux. I'm using Hashcat in Windows because installing the drivers in The-Distribution-Which-Does-Not-Handle-OpenCL-Well (Kali) was getting a bit tedious and it just wasn't working. However, it appears to be working.. sort of. It's using my GPU, which is what I wanted, and it's running a lot faster that my CPU, which is also what I wanted. (CPU got about 4,300 k/s, GPU getting around 12k) However, I don't believe Hashcat is using my GPU 100%. In fact, I think it's using about 2%. Although Hashcat says it's using 98%, Window's Resource Monitor only shows about 2-5%. On top of that, my GPU temperature hasn't changed from its normal temperature like it has when I used it to mine Bitcoin. If you have any more questions, please ask. And again, sorry if this is a stupid question or anything. Thanks!

Almost forgot! Here's my specs:

16gb of RAM
CPU: Intel i7-4700MQ 4 cores (8 logical cores) Generation 4
GPU: nVidia GT 750M 1gb memory
OS: Windows 7 Home Premium
This is all in an Alienware 14 (2013 model) laptop. From what I've read, laptop GPUs don't have near the power of desktop GPUs, but I should be getting more than the 12k k/s I'm getting now, right?

Command I'm using: cudahashcat64.exe -m 2500 -a 0 -d 1 -o textfile.txt WPAHandshake.hccap G:\CustomWPA.txt

Thanks again!

EDIT: Forgot to mention, there is also an Intel HD Graphics 4600 built into the CPU, but the nVidia one is separate.
#2
GT 750M is basically an underclocked, low-power variant of a GT 650. Back-of-napkin math shows that it should get around 13 KH/s, so the 12 KH/s you're seeing is certainly correct.

Whatever you're using to monitor the GPU in Windows Resource Monitor, on the other hand, definitely is not working. Have you tried GPU-Z or MSI Afterburner or something?
#3
(03-18-2015, 09:12 AM)epixoip Wrote: GT 750M is basically an underclocked, low-power variant of a GT 650. Back-of-napkin math shows that it should get around 13 KH/s, so the 12 KH/s you're seeing is certainly correct.

Whatever you're using to monitor the GPU in Windows Resource Monitor, on the other hand, definitely is not working. Have you tried GPU-Z or MSI Afterburner or something?
Just checked it with MSI Afterburner, it's showing 98% usage. Weird, my GPU normally gets up to around 70 degrees C at that usage, but it's only at about 64. Oh well, I guess what I get is what I get. Actually, is there any way I can get more out of my GPU? Or possibly use my CPU along with it? The extra 4k k/s would definitely make a difference at this speed. Thanks!
#4
You should be able to get a little bit more out of your GPU if you add ''-w 3'' to your command line. But keep in mind this may cause display issues, and will likely raise the GPU temperature as well.

You can manually distribute load between cudaHashcat and hashcat-cli using --keyspace, -s, -l, and a little bit of clever math. WPA now uses an AMP kernel so you'll have to convert the keyspace from the "oclHashcat keyspace" to the "real keyspace" in order to distribute between the two devices.
#5
(03-19-2015, 02:47 AM)epixoip Wrote: You should be able to get a little bit more out of your GPU if you add ''-w 3'' to your command line. But keep in mind this may cause display issues, and will likely raise the GPU temperature as well.

You can manually distribute load between cudaHashcat and hashcat-cli using --keyspace, -s, -l, and a little bit of clever math. WPA now uses an AMP kernel so you'll have to convert the keyspace from the "oclHashcat keyspace" to the "real keyspace" in order to distribute between the two devices.
Considering I didn't understand half of that, I think I'll stick with just the GPU for now... lol. Adding -w 3 definitely gives it a boot. Between that and overclocking my GPU, I'm up to 16k k/s. Thanks for your help, once I get a better understanding of Hashcat I'll look into using both the CPU and the GPU. Oh, and cooling shouldn't be a problem even in my laptop. It has pretty good circulation as it is and if I manually set the fan speed fairly high and keep it on a cooling pad, it doesn't get over 60C.