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Comments on: Developer deploys graphics cards to accelerate password cracks

Nothing new here. 

Posted Wednesday 24th October 2007 12:24 GMT

Thumb Down

Sure, they're using graphics cards.

But add on processor boards have been around for years.

Not quite right... 

Posted Wednesday 24th October 2007 12:31 GMT

Stop

The GeForce 8 series of GPUs went on sale in November 2006. The workstation graphic-cards, which are also based on the GeForce 8 (G80) went on sale in March 2007.

Ian.

Exactly... 

Posted Wednesday 24th October 2007 12:43 GMT

@Ian Michael Gumby: Nvidia and ATI with their SLI, CUDA, GPCPU thing have brought to market nothing new. High-end professional graphic cards with many DSPs working parallel existed even many years ago on IBM and Sun systems AFAIK, and they were really fast although very expensive.

Re: Nothing new here 

Posted Wednesday 24th October 2007 12:45 GMT

Maybe, but there is a couple of magnitudes difference between the number of people buying a VGA and an add-on processor board.

New benchmark needed 

Posted Wednesday 24th October 2007 12:57 GMT

Boffin

a good rainbow crack database can break a windows password an a few minutes.

maybe they could try crunching seti units or folding proteins...

so.... 

Posted Wednesday 24th October 2007 13:17 GMT

why isn't my OS running on a couple of graphics cards rather then a motherboard and a graphics card?

@so.... 

Posted Wednesday 24th October 2007 14:07 GMT

...because Windows needs more RAM than is offered on any video cards currently.

@so.... 

Posted Wednesday 24th October 2007 14:08 GMT

"why isn't my OS running on a couple of graphics cards rather then a motherboard and a graphics card?"

Using Vista yet?

different uses 

Posted Wednesday 24th October 2007 14:13 GMT

IT Angle

The GPU is a highly specialized mathematical processor. Whereas a typical cpu has generic functions inherent because of its multiple applications. The reason the gpu is so much faster is that its core is specialized for perfoming highly complex mathematical permutations in nanonseconds. I think many of the people who are saying that this is nothing new are missing the point that while "High-end professional graphic cards with many DSPs working parallel existed even many years ago on IBM and Sun systems AFAIK, and they were really fast although very expensive." The question is whether the tools were available to perform the same functions discussed in this article. Furthermore, the expense is no longer there. Simply buy several cheap GeForce 8 cards and you have a hella system for cracking passwords.

I do think as one poster brougth up that if this could be applied to the several distributed applications(folding@home, seti@home etc etc) it could exponentially increase the rate at which it is processed

RE: why isn't my OS running on a couple of graphics cards 

Posted Wednesday 24th October 2007 14:29 GMT

Because your OS needs a wide range of processor functions from a general purpose processor, the one on your motherboard, whilst the GPUs contain processors optimised to doing some quite specific maths functions. These are analogous to RISC processors, because they only do a few things well they can be much smaller so you can get more of them on a chip for the same cost and power, they are very very good at the instructions they are optimised to but have to emulate the other instructions which is slow and difficult. If your motherboard only had GPUs it would do 3D graphics very fast but your filesystem and other general purpose jobs would run so slowly that the overall effect would be to slow down. This is why GPUs on dedicated graphics accelerators are a good offload from the general purpose processor, to each their own tasks. This is also why things like TCP offload engines for network cards or dedicated game physics processors work well, as they are optimised to deliver one type of job which a general purpose processor is not very efficient at doing.

The argument for GPGPUs is that a graphics processor is basically a really fast floating point maths machine, exactly what you need for applications like climate modelling or finite element materials stress analysis. This allows you to build a very fast grid computer using cheap, commodity general purpose processors on the motherboards to manage tasks, networking, memory and storage but containing lots of GPUs to do the hard maths stupidly fast.

Re: Nothing new here 

Posted Wednesday 24th October 2007 14:37 GMT

Problem in the past with add-in FPGA/DSP/Transputer boards was that they were so complicated to program with such poor tools that it took a couple of years to get an application running on them.

Then the board would either go out of production or not be compatible with the next OS release or Moore's law caught up with you.

If these use regular graphics cards, normal dev tools and keep compatibity on new cards it might be useful.

@E 

Posted Wednesday 24th October 2007 14:42 GMT

Jobs Horns

an 8800GTX has 768MB of RAM - 2 of those would be good for most applications and give huge processing power. I suspect the real problem is the architecture.

GPU as a DSP 

Posted Wednesday 24th October 2007 15:00 GMT

GPUs also have a tendancy to approximate when doing their super-optimised maths: the user just doesn't spot the odd mistake as its small and over one frame later. You can't get away with that in a CPU (as recent Excel programmers should note).

Folding@Home GPU support 

Posted Wednesday 24th October 2007 15:18 GMT

Actually, fah has had ATI GPU (and PS3...) support for quite awhile...

Serial vs. parallel tasks 

Posted Wednesday 24th October 2007 19:19 GMT

Given the same die size, you can either have a few fast cores or a lot of slow cores.

For tasks with a lot of good parallelism, it's much better to have a lot of slow cores. This means graphics, password cracking, etc.

For tasks with very little parallelism, e.g., your browser, e-mail program, etc., it's much better to have one (or two, or four) cores that are engineered to run one thread as fast as possible.

I don't know if the "cores" on a GPU today are general-purpose enough to run an OS, but I'm sure it wouldn't be hard to get them up to that point, given enough motivation. But then you'd be stuck running most of your apps as if you had a 200MHz Pentium.

How many graphics cards would it take... 

Posted Thursday 25th October 2007 01:26 GMT

...to crack my password? Assuming they knew my length, and the character sets I use (e.g. upper/lower case, numbers), there are still 201977518437757778375221238472081529012864009105715786231578624 different possibilities.

How easy would it be to use this for other mathematically intense applications? 

Posted Thursday 25th October 2007 13:52 GMT

Such as folding@home or any of the other distributive applications?

@Jach 

Posted Thursday 25th October 2007 15:10 GMT

Joke

> ...to crack my password? Assuming they knew my length, and the character sets I use (e.g. upper/lower case, numbers), there are still 201977518437757778375221238472081529012864009105715786231578624 different possibilities.

Jach, if they knew your length, they'd be too busy laughing even to bother...

... and for anyone to make a post like that, I think that gives us a strong clue about your length... :-)

Quibble: "a password" rather than "the password"? 

Posted Thursday 25th October 2007 21:31 GMT

If the stored form of the original password is just a cryptographic hash of some sort, a brute-force approach would possibly yield a password (or various passwords) different from the original but which will work anyway by hashing to the same value.

4 graphic cards ? 

Posted Friday 26th October 2007 06:28 GMT

Pirate

Imagine that ! On a system with dual-slot quad cores, that would make 8 CPUs and 4 GPUs, and they want to use that to brute-force PASSWORDS ?!?

Move over you idiots, I've got gaming to do !