The developer provides some plain numbers to show the effectiveness of using the GPU to recover a rar password with four characters:

• ~168 passwords per second on single core of Q6600 @ 2.4Ghz (crark’s result)
• ~325 passwords per second on 8600 GT
• ~3120 passwords per second on ATI HD4850
• ~2075 passwords per second on GTX260/192SP

The performance of the listed ATI card is almost 20 times that of a password recovery where only the cpu is used. The password recovery software is a command line utility and the developer is offering extensive information on the possible parameters that can be used to recover the password. The suggested length of the password should not exceed six characters although it is theoretically possible to start a password recovery for a password with up to 17 chars.

The basic command for the password recovery is:

igrargpu.exe [switch:param] filename.rar

The command

igrargpu.exe /a:b /c:s /min:1 /max:4 archive.rar

will for example check all four letter combinations of lower case Latin characters. Known characters of the password can be added to the command to speed up the recovery attempt.It is advised to check the readme for a detailed overview of all possible parameters. The password recovery program can also use a dictionary based attack with rules. RAR GPU Password recovery should work on most versions of the Microsoft Windows operating system. The portable software is available for download at the developer’s website.

The GPU may fail due to temperature fluctuations and users may experience symptoms like random characters or lines on the screen. The problem is that if customers experience those symptoms the Bios update will not help them anymore and they have to contact Dell support to fix the issue.

Everyone else should check the website to see if their Dell notebook is in the list and update the Bios of its GPU accordingly. The affected notebooks according to Dell are:

• Inspiron 1420
• Latitude D630
• Latitude D630c
• Dell Precision M2300
• Vostro Notebook 1310
• Vostro Notebook 1400
• Vostro Notebook 1510
• Vostro Notebook 1710
• XPS M1330
• XPS M1530

The Bios update will turn on the GPU fan more frequently at half or quarter speed to reduce temperature fluctuations. Dell confirmed once again that this will have no noticeable effect on battery life. New notebooks will be shipped with the updated Bios.

The real question however is which GPUs are affected but there does not seem to be a direct answer for this. There is however the list of Nividia GPUs that have been used in the affected Dell notebooks, here it is:

• 128MB NVIDIA® GeForce® 8400M GS
• 128MB NVIDIA® GeForce™ 8400M GS (64 bit)
• 256MB NVIDIA® GeForce™ 8400M GS
• 256MB NVIDIA® GeForce™ 8600M GS (128 bit)
• 256MB NVIDIA® GeForce® 8600M GT
• 128MB NVIDIA® Quadro NVS 135M
• NVIDIA Quadro FX 360M 256MB TurboCache (128MB dedicated)

My suggestion would be to check your notebook, even if it is not from Dell, to find out if a video card from the list has been used to build it. If that is the case contact the hardware manufacturer to find out how he handles the problem.

More interesting is the Open GL Caps tab which provides extensive information about Open GL capabilities of the video card among them the OpenGL version, texture size and number of texture units. The same tab lists the Open GL Extensions that are supported by the video card.

The core temperature of the video card is always displayed in the title bar of the software and several stress test demos and one named Open GL Burner are provided to stress test the video card.

It’s possible to start multiple demos at once to put lots of strain on the video card to see how it handles the load. The data can be exported in XML format. Another nice feature of GPU Caps Viewer is a links section that provides links to the latest drivers and information about the video card.