Wikipedia:Reference desk/Archives/Computing/2013 March 17

= March 17 =

power consmuption
Which is the power consumption of the ati fire gl v7300??
 * Iskánder Vigoa Pérez (talk) 01:56, 17 March 2013 (UTC)


 * Its datasheet recommends a 450 watt power supply for the entire system. The actual GPU and CPU power consumption varies at run-time based on workload: here's a white-paper, AMD PowerTune.  It seems reasonable to expect the card's total power to exceed 100 watts during heavy use.  Nimur (talk) 02:38, 17 March 2013 (UTC)

thanks!! could be any situation, or any tiny chance, in which this card colud be a better choice than a quadro 2000???
 * Iskánder Vigoa Pérez (talk) 03:29, 17 March 2013 (UTC)
 * Short answer: no. The FireGL7300 has fewer features and lower performance - even if you're referring specifically to the Quadro 2000 and not the current Quadro K2000, with Nvidia's new Kepler architecture.
 * FireGL7300 is older technology, has fewer hardware capabilities overall, contains support for older revisions of common APIs like OpenGL and DirectX, does not appear to support any GPGPU APIs, and has lower performance across the board. It would at least be a fair comparison if you compared one of the FirePro series to the Quadro 2000.
 * I took a cursory look at each company's current product lineup, and I would say that AMD/ATI's closest match for Nvidia's current Quadro K2000 is the FirePro W7000. There is not an easy apples-to-apples comparison, but these two products have a large number of specs in the same ballpark.
 * Now, whether those features are something you need will affect whether any card is "better." If you do not need a GPGPU processing engine, then there is no sense paying a premium for it.  And you asked if there is any situation where one could prefer the 7300...well, there are a lot of scenarios...!
 * I am of course partial to CUDA, so I lean towards Nvidia's products, but I can admit that this is vendor lock-in; I am unwilling to convert my old CUDA code to OpenCL, so I have never performed an actual, fair benchmark comparison on my own code. Many friends and colleagues highly recommend OpenCL, and because it is implemented as free software, I can see much merit in that platform.  ATI has strongly embraced OpenCL, while Nvidia's support for it is always secondary to CUDA.
 * Many friends and colleagues profess a bias towards ATI or Nvidia, because of the belief that they one company produces more stable graphics drivers (though I have no data to confirm or refute these claims). Any of these can be construed to make the FireGL7300 a "better" card, despite any technical shortcoming.  I still operate a GeForce 5800 on one machine, and it is a "better" card than any other available today, despite its archaic performance metrics -because it was the last Nvidia card that used the AGP interface, and I refuse to let one of my perfectly functioning machines succomb to the garbage bin.   Nimur (talk) 04:27, 17 March 2013 (UTC)


 * Thanks again, I was thinking something like that already, just wanted to be sure… my current cards are Quadro 2000 (without the k) and, at least for now, I’m not interested in move on to the newer ones, but I have this chance of get a “almost non used” firegl v7300 and almost for no cost, and was going in one of two directions, 1 : resell it or give it to some friend or something or 2: get rid of one of my “heavy used” quadro and put the GL instead… but I gest it’ll be the first one
 * but any way… it would be very helpful a more precise power consumption… thanks for you r  comprehensive answer
 * Iskánder Vigoa Pérez (talk) 23:43, 17 March 2013 (UTC)

Moving a large number of files
My second internal drive has about 380GB in about 320,00 files that I want to move to an external USB 3 drive so I can reformat the internal drive and copy the files back. The external drive is fast enough, but there is a lot of overhead in creating all of those files. A straight copy in Windows says that it will take more than 1 day. Is there a more practical way to do it? Bubba73 You talkin' to me? 04:31, 17 March 2013 (UTC)
 * Let me back up to the reason I want to do this - there should be a better solution. This is the second internal HD and I want to remove the Windows, Program Files, and Program Data folders.  If I try to remove them, for many of the files it says that I need the permission of TrustedInstaller to delete them.  Is there a way for me to get permission from TrustedInstaller?  (I don't know what that is.)  Bubba73 You talkin' to me? 04:47, 17 March 2013 (UTC)


 * I've found that using the command line copy/move commands are lot faster than using the GUI to copy the files. You could try that.  RudolfRed (talk) 04:48, 17 March 2013 (UTC)


 * I've just found this which should tell me how to do the second thing. Bubba73 You talkin' to me? 04:50, 17 March 2013 (UTC)
 * Well, my Windows 8 system is different. It says to right-click on the folder, properties/security/advanced button/owner tab, but there is no owner tab.  Bubba73 You talkin' to me? 05:07, 17 March 2013 (UTC)


 * It sounds like you want to create a full disk image. On Windows, you will need to use a separate program for that task (it is not built in to Windows).  Many free and commercial options are available: we have a comparison of many tools.  Nimur (talk) 04:53, 17 March 2013 (UTC)


 * Actually I don't want to do that - I actually want to get rid of the Windows, Program files, and program data folders that are on my second internal hard drive. And it won't let me because I need permission of TrustedInstaller (the owner).  Bubba73 You talkin' to me? 05:07, 17 March 2013 (UTC)


 * If I'm understanding this correctly, you want to grab a bunch of files (which is just a selection of files and not everything on the drive), move them to an external drive, and then format the original drive which would wipe it. Then move those files back.  This would leave the internal drive with just those files and no remnants of the OS.  Right?  Dismas |(talk) 05:12, 17 March 2013 (UTC)


 * Right, and I can't delete them directly because they are owned by TrustedInstaller. I tried two sets of instructions about how to do that, but they don't match what is on my computer. Bubba73 You talkin' to me? 13:43, 17 March 2013 (UTC)
 * And in case you are wondering how it got that way, when I added the second internal HD I mirrored the C drive to it. The idea is that if the C drive failed, I could just swap and be back up.  Well, since then I've installed Windows 8 and most of the programs have been updated, so the system stuff on the second internal HD is way out of date and will never be used. Bubba73 You talkin' to me? 17:53, 17 March 2013 (UTC)


 * Windows' estimates about how long things will take aren't very reliable. I don't know of a better way than using rsync or Robocopy. -- Finlay McWalterჷTalk 11:49, 17 March 2013 (UTC)
 * I started it and after a while it got 1% done, so it may not be accurate, but it was going to take a long time. Bubba73 You talkin' to me? 13:43, 17 March 2013 (UTC)


 * I don't really get why you can't take ownership, presuming you're using an administrator account. I'm using Windows 8 right now and taking ownership is right there. Click on the security tab, click on the advanced button (which says it's for 'special permissions or advanced settings' so is kind of a give away) and it should list owner. Right next to the owner there should be a 'change' you can click on. This has changed slightly since Windows 7 (and previous versions) but it's one of those things which has changed so little that it's easy to find (compared to some other things). There are of course other ways to take ownership. Nil Einne (talk) 18:17, 17 March 2013 (UTC)


 * But after clicking on that "change", I don't see anywhere to change it. It has buttons "object types", "locations" and "check names" and a field "enter the object name to select", but I don't see how to change the owner.  Bubba73 You talkin' to me? 18:22, 17 March 2013 (UTC)


 * For the copying, you could use a program like 7-Zip to compress the files onto the new hard drive (maybe with zero compression - the point is that this would only write one file and hence be much faster than copying them one by one. I have always been annoyed about how slow this is in Windows and I am amazed to hear that they have not yet fixed it). You could also safely delete all "temporary internet files" before copying; that directory (at least on older Windows versions) tends to hold a vast amout of very small files that it takes an eternity to copy. Jørgen (talk) 20:47, 17 March 2013 (UTC)


 * I've just been testing my various drives for the speed of opening and closing files in Windows, and I have some unusual results. I'm double-checking them before I ask about them here, but some drives take on the order of 0.1 second overhead whereas others are on the order of 0.001 seconds.  Bubba73 You talkin' to me? 01:49, 18 March 2013 (UTC)

Changing the USB drives from "quick removal" to "better performance" made the difference. Bubba73 You talkin' to me? 02:00, 19 March 2013 (UTC)


 * And I got the process done in a reasonable amount of time and recovered over 200GB of HD space. Bubba73 You talkin' to me? 05:03, 19 March 2013 (UTC)

Book recommendation request
I could go wandering from article to article on Wikipedia and get very lost and very confused in no time, so I'm looking for a book recommendation or primer on cyber security, hacking, what part algorithms play, etc. I'm attending computer engineering classes right now and am in my first year or so (part time so it's hard to say), so I don't need the "Dick and Jane" version of things. Is there anything like this out there? Maybe a text book that I can pick up for cheap? Dismas |(talk) 04:45, 17 March 2013 (UTC)
 * You might find that The Code Book meets some of your needs.--Phil Holmes (talk) 11:43, 17 March 2013 (UTC)


 * Bruce Schneier's Applied Cryptography or Practical Cryptography, and Ross J. Anderson's Security Engineering. -- Finlay McWalterჷTalk 11:45, 17 March 2013 (UTC)


 * Applied Cryptography is the bible of cryptography reference texts. It explains everything, however it's big and pricey. I've read The Code Book and I remember liking it, but if I remember right it's more in the genre of nonfiction like Malcom Gladwell and not as much a reference text. I think Practical Cryptography is another good choice. If you want more than just cryptography or codes though, you might find a sensationally titled, but nevertheless good overview in Hacking Exposed 7 (there's a whole series, this is the most recent). I have an old used copy somewhere and I found it interesting.


 * Are there any specific areas you're interested in? I know of some online resources that are really good on specific, small topics, if there were a few of those you were interested in. I know some of our articles, math ones particularly, are not good introductions to a topic. Shadowjams (talk) 00:58, 18 March 2013 (UTC)


 * Thanks for all the responses!!
 * There are no specific areas, I guess. I don't think I have the aptitude in math to get a degree in cryptography but I'd like to know more about it.  Like when groups hack in to Twitter or Sony or the local utility company.  I'd like to know roughly how they did it.  I don't necessarily want detailed specifics of how to do it, partially because I'm not sure that I'd understand them, but I'd like to know more than "Such-n-such was hacked and a million credit card numbers were stolen".  Do they just start a PuTTY session and start trying passwords or what?  Also, I'm often asked by friends various questions about how things work, and I'd like to be able to break it down for them. (One recent one was what IP addresses are)
 * And yes, our technical subject articles get very technical very quickly. Salt (cryptography) and Hash function were two that I tried to slog through last night.  Thanks again, Dismas |(talk) 01:55, 18 March 2013 (UTC)
 * Most security breaches have nothing to do with cryptography; they usually involve social engineering and/or exploits of the sort listed in Category:Computer security exploits and its subcategories. SQL injection is currently a common technique—I think that's how the PlayStation Network was hacked, though oddly the Wikipedia article doesn't say. There are attacks that involve nontrivial cryptanalysis, such as cracking of wireless networks and rainbow tables, but generally the people that do it don't know anything about cryptography—they use software written by someone else. -- BenRG (talk) 02:42, 18 March 2013 (UTC)

One more question, would picking up a copy of 2600 be a good idea? Dismas |(talk) 01:55, 18 March 2013 (UTC)
 * It's a fun read sometimes, picking up a copy will give you some ideas about how systems work. Although articles in it are hit and miss. Sometimes people write articles about really basic methods (or they feel basic to me) but then sometimes I'll hear about some interesting tool or configuration, so there's that. A good primer on cryptography is important to know, not the math so much, but just how the primitives fit together and what you can and cannot expect. But as Ben says, cryptography isn't the weak link. The sophisticated attacks you hear about leverage some vulnerability and go from there. You should read any of the books or blogs about penetration testing. Shadowjams (talk) 15:20, 18 March 2013 (UTC)

How to tell if my graphics card supports OpenGL 2.1 and GLSL 120 ?
ATI Radeon Xpress 1100

Driver Date: 3/14/2007

Driver Version: 8.360.0.0

I tried to update the driver, and it said it was already up to date. There appear to be different versions of that card, not all of them support OpenGL 2.1 and GLSL 120. How can I tell, for sure ? StuRat (talk) 10:24, 17 March 2013 (UTC)


 * Is it the notebook or desktop one? And which OS? Shadowjams (talk) 01:03, 18 March 2013 (UTC)


 * Desktop (compact form), Windows 7. StuRat (talk) 01:33, 18 March 2013 (UTC)


 * Is this the driver? Shadowjams (talk) 01:55, 18 March 2013 (UTC)


 * Well, "ATI Radeon Xpress Series" was listed there, along with many other series, but I think I just have the default driver that came with the device. Would downloading that driver add OpenGL 2.1 and GLSL 120 support ? StuRat (talk) 02:44, 18 March 2013 (UTC)
 * Ah, here we are. Sorry for the delay, StuRat, I couldn't track this tool down: ATI GPU Services Library...  the tool to determine at run-time whether your current hardware and software support a particular feature-set.  Remember, OpenGL is an API, not a hardware specification.  Technically, your system can "support" any revision of OpenGL at all, but if the hardware and low-level driver is unable to accelerate a particular feature, it is often better to design your application to avoid that feature.  OpenGL itself has numerous methods to verify if an extension is present; start with the top-level documentation.
 * According to the programmer reference manual, your GPU is a member of a product series that supports ATI's DirectX 9 Vertex shader model 3, documented here. As with any shader program, you need to pay close attention to hardware and compiler limitations: just to remind you, the OpenGL Programming Guide from ATI: reminds you that shaders are programs that may or may not run with acceleration.  "The driver will always report the word “software” in the info log if the shader forces the driver to not render fully hardware accelerated."
 * Finally, if you're asking about OpenGL 2.1 as a user rather than as a developer - the short answer is, sorry, your Xpress 1100 is a few years old and was never the top-of-the-product-line-up, even when it was new. It was marketed as an integrated GPU - a solid sort of work-horse, but not a high-performance or gaming processor.  It may support OpenGL2.1 and DirectX9, if you have the most current drivers; but its performance will be low compared to most other GPUs.   Nimur (talk) 04:19, 18 March 2013 (UTC)


 * Thanks. I need those capabilities as a developer.  I'm taking an online edX Computer Graphics class, which uses Microsoft Visual Studio 2012 for Windows Desktop.  It's giving me errors, and they suggested that those may be from a lack of support for OpenGL 2.1 and GLSL 120 in my graphics card/driver.  So, it looks like I need to go buy a new card, right ?  (I have another question on that, down below a few Q's.) StuRat (talk) 06:12, 18 March 2013 (UTC)

iPod Touch - Moving a File to a Folder
On the iPod Touch, how do I move a file to a folder? I have files which I have already transferred from my PC to my iPod (not music files, these are documents, because I use it for work). I also have lots of folders I have been able to make on the iPod itself. However, I am unable to find a way to actually organize my documents and put them all in the folders, so all I have is a bunch of empty folders and a disorganized mess of documents. If I can make folders, then there must be a way to move those documents into them. Can anyone help? KägeTorä - (影虎) ( TALK )  11:30, 17 March 2013 (UTC)