Wikipedia:Reference desk/Archives/Computing/2008 April 11

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April 11[edit]

RAM problems freezing the computer[edit]

My computer freezes often in games. Works fine for a while, freeze for a ~2 seconds and then unfreeze by first speeding up (to display what he forgot to display) and then works normaly for another several minutes. It shows most obviously in Audiosurf.

Two friends told me the problem was most likely in improper CAS latency times but werent able to give me exact settings I should use.

Now, the setup: Motherboard is TF570 SLI A2+ with Athlon 64 X2 4000+ CPU Bios is N57LA-A2T Memory is 4 * Transcend JM800QLJ (1GB, the packaging says 5-5-5) (Yes, I am away that WinXP doesnt see all 4GB but only 3.25. I think thats better than 2GB and am not yet convinced switching over to Vista is a good idea.)

The Bios has way too many settings, but I wrote all of them down (current setting are bolded):

CAS Latency: Auto 3 4 5 6

DRAM Command mode: Auto 1T 2T

TwTr Command Delay: 1 2 3

Trfc0 for DIMM0 75 105 127.5 195 327.5

(same for other 3 DIMM channels)

(Twr) Write Recovery: 3 4 5 6

(Trtp) Precharge time: 2 3

(Trc) Row cycle time: 11 to 26

(Trcd) RAS to CAS R/W delay: 3 4 5 6

(Trrd) RAS to RAS delay: 2 3 4 5

(Trp) Row Precharge Time: 3 4 5 6

(Tras) Minimum RAS active time: 5 to 18 — Shinhan < talk > 21:43, 10 April 2008 (UTC)

The first thing to do is see if it's the RAM that's the problem. Download Memtest86+ and run it for a few hours -- 24 hours if you can stand to not use your computer for that long. If it comes up clean, it's probably something else that's the problem. --Carnildo (talk) 21:15, 11 April 2008 (UTC)[reply]

floppy recovery[edit]

I bought a USB floppy drive because I have a shoebox-ful of files that I'd like to recover. Alas, it cannot read MacOS 800k discs (and does not say so on the outside of the box). Guess what format most of those files are in! Any advice? —Tamfang (talk) 01:06, 11 April 2008 (UTC)[reply]

Return it and buy one that can. StuRat (talk) 01:24, 11 April 2008 (UTC)[reply]
Brilliant. Now, do you happen to know of a maker of such a device? —Tamfang (talk) 03:11, 11 April 2008 (UTC)[reply]
Apple might have a vendor. Just how obsolete are they ? StuRat (talk) 03:38, 11 April 2008 (UTC)[reply]
I think you need more than just a floppy drive that can read 800 K disks, your OS needs to support the filesystem those disks use. Rilak (talk) 04:02, 11 April 2008 (UTC)[reply]
Those would be GCR disks. You need some specialty hardware for those, like a CatWeasel. That or an old Mac that still works... --tcsetattr (talk / contribs) 04:37, 11 April 2008 (UTC)[reply]

Buy any old Mac for $10. Then, do one or more of: 1) Use LocalTalk AppleTalk networking if your newer machine supports it; 2) Use Ethernet if the old used Mac support it. 3) Use the old Mac to convert the data from the 800K floppies to the newer 1440K format then read them anywhere. 3) If your newer machine supports SCSI, connect an external SCSI hard drive to the old machine, archive all the floppies onto that, and move the drive to the newer machine. 4) Or, after archiving, use the older system in target disk mode connected to the new machine. 5) If the old machine uses an ATA internal drive but won't support target disk mode, archive all the floppies to the old machines ATA drive, then buy an external drive mounting box, take the hard drive from the old system, mount it in the box, and mount that drive on the new machine. 6) Use the internet as intermediate storage. 7) Use FTP. 8) Use a serial line and Kermit. Other possibilities exist, but you get the idea: they all depend on that $10 used Mac.

Atlant (talk) 11:49, 11 April 2008 (UTC)[reply]

A mac for USD 10? awesome! where do I sign up? Kushal 15:29, 11 April 2008 (UTC)[reply]
From time to time, they turn up for free at our local landfill's "swap shop" (drop off your junque, claim someone else's abandoned treasures). I saw a Color Classic" not too long ago.
Atlant (talk) 17:48, 11 April 2008 (UTC)[reply]

warning: function call has aggregate value[edit]

I'm once again doing what I'm not supposed to do. I have to (against my will) write a plugin that implements an OS service. The program for the plugin requires that the program be written in C. The OS service requires that the implementation be written in C++. I have got it to compile and run while including both the C structure and the C++ classes. However, I've hit a snag that I don't think can be subverted. One of the functions (one that I cannot avoid using) has an aggregate value. That is fine for C++. However, when I use it, the program segfaults. The function in question (in case anyone cares) is KWallet::Wallet::LocalWallet(). The plugin is for libpurple. I understand why it is segfaulting, but I don't see how to avoid it. Does anyone know of a cute trick for turning an aggregate value function into a primitive value one (this returns a QString, but a char* would be nice). -- kainaw 02:22, 11 April 2008 (UTC)[reply]

Returning an aggregate is valid in C and C++, so that's not necessarily a real problem. It's not even included in the set of warnings enabled by -Wall. What you need is a bridge function, compiled as C++ with extern "C" linkage, which gets the QString, converts it to char *, and returns it. Your C code can call that function. (The calling C code may also be responsible for free()ing the memory, if it was dynmically allocated in the bridge function. Or, if the returned pointer points within a C++ object, you have to be careful to keep that object alive until the C code is done with it.) --tcsetattr (talk / contribs) 02:58, 11 April 2008 (UTC)[reply]
It turns out that the segfault was because the function was trying to open a modal Qt window and the application is GTK. So, I'm back to hunting down solutions to problems that shouldn't exist. -- kainaw 12:27, 11 April 2008 (UTC)[reply]

useless cd[edit]

IT is said that if the computer shuts down accidentally while copying files into a cd then the cd will show 0 bytes space afterwards and thus will become useless. 1 why does this happen? {it has happenad twice to me} 2 is there a remedy? 3 most imp, does this happen to rewritable discs as well? --scoobydoo (talk) 06:25, 11 April 2008 (UTC)[reply]

1. The lead-out (the end of a CD, which, if I remember correctly, contains the end-of-CD data) is not written, and if the system can't find it, it assumes the disc is corrupted.
2. Buy an UPS.
3. Yep. The only difference is that rewritables can be reused. (Just erase them before.)
--grawity talk / PGP 10:17, 11 April 2008 (UTC)[reply]

Mirror for ftp.digital.com?[edit]

Does anyone know if there is a mirror for ftp.digital.com? The server running this site has been retired by HP. Thanks. Rilak (talk) 07:13, 11 April 2008 (UTC)[reply]

I don't know what you are looking for, but there are some answers to your question in this thread: http://groups.google.com/group/comp.sys.dec/browse_thread/thread/2ee0343c97e0cf8a. Also, gatekeeper.dec.com is still around, though it's probably not what you are looking for. Riordanmr (talk) 00:41, 16 January 2009 (UTC)[reply]

Looking for a programming language.[edit]

Although I don't have any particular long term aims as to the kind of programs I want to make (mostly I have been experimenting with small random word / name generators, basic ASCII/Unicode menu interfaces), I feel uncomfortable with the two programming languages I have made any real investigation into. Here are my thoughts:

a) C. What I like about C is that the syntax is compact and there's a basic set of data types and control structures that tend to stick to strict rules; you have to state a lot of things in one particular way which makes code much easier to follow in my opinion. A line of code that looks obfusticated can be broken down into its components fairly easily and problems can be solved, I feel, far easily. On the other hand, its "rigidity" makes what can be trivial exercises in more modern languages more of a challenge - compare an algorithm required to reverse a string in C with some quick and easy method on the string object in Ruby: string.reverse.

b) Ruby. I like Ruby because it offers some very convenient methods for manipulating data objects such as strings and arrays. Other data types like Hashes can of course be manufactured in C, but I'm sure you can appreciate that they are much more elegant in Ruby. The OO paradigm is obviously very attractive (although I'm not too familiar with it) and in general I like the ease with which so many things can be done in Ruby. However, I don't like the fact that programs are run through an interpreter, I don't really like duck typing, and I also don't like the ten billion ways you can do the same thing.

I'm looking for a language that is less bloated and a bit more strict and powerful at the basic level (like C) but uses more modern programming approaches (classes, garbage collection e.t.c) and has a decent standard library of functions. Correct me if I'm wrong, but the following candidates spring to mind:

i) C++ : Don't know much about this.

ii) Python: Similar to Ruby, but more streamlined and well established? Does this compile? I am very interested in this.

iii) Java: Don't know much, but it's interpretative?

iv) C#: Requires .NET support, correct? Interpreter or compile?


If none of the above made much sense, I'm basically looking for a minimal, "modern" programming language that is geared towards the development of compiled executables on the Windows platform. Thanks Damien Karras (talk) 13:18, 11 April 2008 (UTC)[reply]

Python is an interpreted language. You can think of C++ as C with classes. You'll have to do your own garbage collection with that. Java and C# don't fit it to either the "compiled" language pigeon hole or the "interpreted" one. There was a discussion about it on here a little while ago - about a week ago. Why is it that you don't like interpreters exactly? —Preceding unsigned comment added by 194.223.156.1 (talk) 13:51, 11 April 2008 (UTC)[reply]

Have you looked at PHP. It is syntactically very similar to C/C++. It has a lot of helper functions for many things that you appear to be doing. However, it doesn't lend itself to compiling into a standalone executable. Like other interpreted languages, you have to run your script through the PHP interpreter. -- kainaw 13:59, 11 April 2008 (UTC)[reply]
That's generally what I'm trying to avoid, unfortunately. PHP strikes me as being very popular in web development - does it hold its own as a programming language for large and efficient programs, like, say - C does? Damien Karras (talk) 14:07, 11 April 2008 (UTC)[reply]
Did you read the todays xkcd comic? Second part is on differences between C and Python :) — Shinhan < talk > 14:51, 11 April 2008 (UTC)[reply]
Correct. PHP is primarily a web-development scripting language. However, I use it primarily as a quick-and-dirty prototyping tool. I write most projects in PHP first to demonstrate proof-of-concept. Then, when the algorithms work and everyone is happy, it is very easy to rewrite them in C/C++. -- kainaw 18:07, 11 April 2008 (UTC)[reply]
I use python on a daily basis. It doesn't (as far as I know) compile to windows .exe; but it does compile to bytecode. The big advantage with python is ease of development - almost everything you could want is available as a python library. I'm also skeptical about duck typing (I don't like the idea of mixing up a LinkedList object and a FileSystem object and the interpreter saying "this object read()s like I expected, I wonder what this delete() method does..."). But it's other ideas are very good - the "only one correct way to do things", its love of lists and its (over)use of exceptions works well. As for speed, I've never had any problems, though some operations are quicker than others (map is faster than for loops, for example). The other languages - Comparison of programming languages is a quick win. Don't use C# if you want your code to be cross platform. --h2g2bob (talk) 23:38, 11 April 2008 (UTC)[reply]
I've used C, Python, and Ruby, among other languages. C is simply tiring; you spend a lot of time re-solving problems that have been solved long ago. Of course, if you need raw speed, C is still the winner.
I know exactly what you mean by ten billion ways to do the same thing in Ruby. I once tried to switch from Python to Ruby because Ruby was more exciting, but I eventually came back to Python because their philosophy of "there should be one obvious way to do it" really works. (h2g2bob didn't say it quite right -- saying "only one correct way" instead of "obvious way" makes me think of a straitjacket language like Java. Python doesn't limit your choices, it just drops big hints about what the right choice is.) rspeer / ɹəədsɹ 10:19, 13 April 2008 (UTC)[reply]
Oh, and also, if the speed of Python's bytecode interpreter isn't enough, there's a library called Cython that lets you write C-style declarations in your code and compile it. The more you declare, the faster it runs. I haven't used it much, though, so I don't know if there are drawbacks to Cython that I haven't encountered. rspeer / ɹəədsɹ 10:29, 13 April 2008 (UTC)[reply]

Remote shutdown on Windows networking[edit]

I have a PC running Windows XP Professional in my office which is at the end of the garden. It is connected via a long cable to the router/ADSL modem in the house. Also connected to the router/ADSL modem, is the house PC running Windows XP Home. I use file and printer sharing so I can access my work from the house PC if I need to. In times of bad weather I often do my work on the house PC, but if I need a document or file, I then have to put on boots and trudge to the end of the garden, just to turn on the office PC. I have been investigating using a Wake-on-LAN utility to avoid the walk in the wet and the mud. I found one that works and I can start the office PC without any problems, but if I use it to shutdown the office PC, the shutdown command is rejected with "Access is denied". I get the same problem if I type:

c:\windows\system32\shutdown -s -f -m \\OFFICE

in a DOS window.

I can't think of a good reason why the remote shutdown won't work. Both PCs are in the same workgroup. Both usernames are the same with no password set. Will this ever work? Is there something else I can try?

Astronaut (talk) 14:29, 11 April 2008 (UTC)[reply]

First off all, if you want a dead-certain method of shutting down your computer remotely, you can always use a VNC program (that is, start up the remote desktop client, and shut it down as you would if you stood in front of it), though that might considered overkill for this issue.
Now, to your problem at hand. Try doing that command with slashes ("/") instead of dashes ("-", and hey, that rhymes!). Like so:
c:\windows\system32\shutdown /s /f /m \\OFFICE
Many a times has and old unix-coot like myself been annoyed with that convention, but c'est la vie. I don't know if it will change anything, but what the heck, it's worth a try.
If that's not it, to me it sounds like permissions issue. I'm not sure how the fancy windows remote computer doo-dads work, but make sure the account (on the foreign computer) has enough priviliges to shut the computer down from the command-line.
Now, you asked for an alternative method, so lets get creative: Install cygwin with packages "openssh" and "shutdown" selected, configure ssh to run as a service, and then you can ssh into it using PuTTY and bim-bam-boom "shutdown now" will kill your computer. If you're a bad-ass h4xxor, this wouldn't be to hard. However, if you're not all that experienced, this is fairly advanced stuff. Since you installed Wake-On-LAN I'm guessing you're more the bad-ass hacker type, though :) --Oskar 18:26, 11 April 2008 (UTC)[reply]
Also, if you're totally nuts: circuit breakers. Dude, bad-ass. :D --Oskar 18:33, 11 April 2008 (UTC)[reply]
When I type "shutdown -?", the help provided indicates I should use "-" for the command switches; but I gave the slashes a go just in case. In fact I strongly suspect this problem has something to do with permissions/privileges, so I had a fiddle around with the group policy editor on the office machine (it's got XP Pro remember), and found a setting to permit other computers on the network to shut it down. Made no difference at all - still getting "Access is denied." I thought about remote desktop software. If I can a free one to try, that would be great - any suggestions would be appreciated.
In fact, I've already tried the "bad-ass" circuit breakers method - I've tried leaving the office PC on 24/7, but the power to the office occasionally trips out. That is when I need to put the boots on and trudge down to the end of the garden in the rain just to turn the damned thing on again. Unfortunately, that kind of thing is bad for the PC and I would rather have it under some control from the house.
Astronaut (talk) 20:08, 11 April 2008 (UTC)[reply]
I've used this VNC product. --LarryMac | Talk 20:40, 11 April 2008 (UTC)[reply]
Yes, RealVNC is a fine product, it's dead-easy to install and dead-easy to use. Some people like other VNCs because they are faster (like TightVNC), but that makes virtually no difference on a local network. If you're comfortable with that solution, it works great. Note that it is not the most secure product in the world, so if you only intend on using it on your local network, I'd recommend configuring it so that it will only accept connections from the local network (you can do that in the GUI, specify an IP for the local network and a subnet mask). RealVNC is totally free (in the speech sense, it's open source). Good luck! --Oskar 23:03, 11 April 2008 (UTC)[reply]

How to convert VHS to put on youtube[edit]

So how do I convert VHS tape? I have a tape player and a DVD player plugged into the same telly. I presume I can record from the VHS to the DVD, put the DVD it in my PC and convert it to the required format somehow? —Preceding unsigned comment added by I am not a dog (talkcontribs) 14:30, 11 April 2008 (UTC)[reply]

Can you record TV shows on your "DVD player" and watch them later from the "DVD player"? If no, you will need additional equipment. I like watching youtube videos and encourage you to upload your videos to youtube. Looking forward to watching your videos, Kushal 15:19, 11 April 2008 (UTC)[reply]
If you have a TV tuner card in your computer, you can plug your VCR right into your PC and record the contents digitally, then you can upload to YouTube. Useight (talk) 15:51, 11 April 2008 (UTC)[reply]
I have a DVD recorder on my TV. I record my camcorder videos on DVD using that. Then, I put the DVD in my computer and use DVD:Rip to rip the videos to avi files. Then, I upload the avi files to YouTube. Lately, I've been shooting small mpg videos on my digital camera and uploading them without any conversion. -- kainaw 15:53, 11 April 2008 (UTC)[reply]

Document Management[edit]

We are searching for a fully integrated document management system for our organisation (60 concurrent users). We are unable to decide, so here I am to get your help.

Requirements: 1. Capture documents from Email, Fax, Scanner 2. Workflow 3. Drag and Drop, Preview documents 4. Search / Retrieve documents, files 5. Performance 6. Look and Feel

We have seen demos: K2, Filebound, Spring CM, Document locator, Hitech and Laserfiche; we feel Laserfiche is a better product of them all. Our Intranet is hosted by Sharepoint. There are plug-ins available for Sharepoint's missing features like: Capture documents (Knowledgelake), Tree structure (Wisdom) and Preview (BA-Insight).

I would like to know which is better on functionality? [LASERFICHE] or [SHAREPOINT with Add-ons]? Slmking (talk) 16:15, 11 April 2008 (UTC)[reply]

PS3 ~ TFT Monitor[edit]

Hello,

I am planning to host a small PS3 lan party with my friends and i want to know what kind of cable I should get to attach my 60gb PS3 (UK) to this monitor,

http://www.ebuyer.com/product/138535

I am thinking some kind of HDMI to VGA but am not sure. Plus where would I get one of those on the cheap. (I have to pay for beer, driving lessons and bosom shaped cake as well)

84.13.26.33 (talk) 18:23, 11 April 2008 (UTC)[reply]

I own a PS3 and may be able to assist you. Is your monitor High Definition? If so, you may be able to do a direct HDMI connection. STORMTRACKER 94 Go Irish! 19:43, 11 April 2008 (UTC)[reply]
HDMI to DVI should be easier/cheaper, if your monitor supports DVI (and just about every LCD monitor does). See our article on HDMI. The two formats are compatible so you just need a simple adapter; only thing that would be limited is that it's not encrypted, so the PS3 will refuse to play Bluray movies at full resolution and such. -- Consumed Crustacean (talk) 00:52, 12 April 2008 (UTC)[reply]
Awesome thanks guys, this should do shouldn't it?

http://www.ebuyer.com/product/130512 —Preceding unsigned comment added by 84.13.26.33 (talk) 19:01, 12 April 2008 (UTC)[reply]

Yep. -- Consumed Crustacean (talk) 03:05, 13 April 2008 (UTC)[reply]
And good luck with the bosom-shaped cake, too! 81.187.153.189 (talk) 10:14, 13 April 2008 (UTC)[reply]

Razer Tarantula or Razer Lycosa[edit]

Which of these two gaming keyboards are better? The lycosa is cheaper and as far as I can see almost the exact same as the tarantula (except the lycosa has keys with backlights), but there must be something to justify the $100 ~ £50 price tag, and why there always out of stock everywhere.

Lycosa http://www.razerzone.com/index.php?main_page=product_info&cPath=2_21&products_id=76

Tarantula http://www.razerzone.com/index.php?main_page=product_info&cPath=2_21&products_id=40 —Preceding unsigned comment added by 84.13.26.33 (talk) 18:48, 11 April 2008 (UTC)[reply]

Music in Powerpoint[edit]

Help! Can someone tell me how to play music in a slide show without it stopping at the next slide? So far, I've only managed to make it not stop after the next click, but for some reason it always stops after the next slide. Thanks! --JDitto (talk) 19:23, 11 April 2008 (UTC)[reply]

Liberally paraphrased from the PP help system - Right-click the speaker icon and then click Custom Animation. In the Custom Animation task pane, right click the music file name and select Effect Options. Under Stop playing, select After, and then set the total number of slides the file should play on. --LarryMac | Talk 19:32, 11 April 2008 (UTC)[reply]

Firewire OS[edit]

How well can an operating system (say, vista) run off a firewire hard drive? --Randoman412 (talk) 19:41, 11 April 2008 (UTC)[reply]

Depends on the computer and OS. A Macintosh can run MacOSX off a firewire drive with no trouble; if the computer supports booting from firewire, Linux will run just fine. I wouldn't trust Windows to run properly off anything except the primary partition of the first internal hard drive. --Carnildo (talk) 21:22, 11 April 2008 (UTC)[reply]
Why? Windows NT can run just fine from any drive - no matter if it's primary or secondary. (Don't know about FireWire, however.) --grawity talk / PGP 16:41, 12 April 2008 (UTC)[reply]

Default font[edit]

I'm using MS Word 2004 on OS X. I've set Lucida Grande as my default font, but when I start using the Russian keyboard, it switches to Times New Roman and doesn't let me type in Lucida Grande. (Oddly I don't have this problem with the Greek or Hebrew keyboards.) How do I get it to use Lucida Grande for Russian? --Lazar Taxon (talk) 22:27, 11 April 2008 (UTC)[reply]

Hm, as far as I know, MS Word doesn't support many fonts in non-Latin alphabets. However, according to this, MS Word should support the listed fonts. Keilana|Parlez ici 03:26, 12 April 2008 (UTC)[reply]