Wikipedia:Reference desk/Archives/Computing/2011 May 17

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May 17

Dell PowerVault TL4000 Tape Library - Maximum Power Consumption

Good Morning, Everyone!

  I've been looking at the Dell PowerVault TL4000 Tape Library, but haven't been able to find its wattage-rating anywhere on the Dell website. All the specifications except wattage are stated. Does anyone here know what's the TL4000's wattage?

  Thanks as always. Rocketshiporion♫ 01:03, 17 May 2011 (UTC)

Watts = Volts * Amps, so from the figures they gave it's between 130 and 168 watts depending on your input voltage.  ZX81  ^talk 01:30, 17 May 2011 (UTC)

AFAIK Ultrium tape drives consume around 70-80W of power each, so it seems unlikely to me that a tape library with four half-height LTO-5 drives in it would consume just 168W of power, but I could be mistaken... Rocketshiporion♫ 09:21, 17 May 2011 (UTC)

This product spec (page 32 / 36) shows a variety of Ultrium drives running at 20-40 W under typical usage (30-55 W at max load), so I suspect your intuitions are wrong. Something about 130-170 W seems reasonable for a 4-drive system given those single drive numbers. Dragons flight (talk) 09:43, 17 May 2011 (UTC)

Can anyone recommend any books about Gynoids which are female robots with a human appearance

Removed duplicate question. Answers on science desk. Please do not double post.--Shantavira|^{feed me} 07:00, 17 May 2011 (UTC)

Laser mouse WITH a mini-trackball? Does it exist?

Has anyone ever seen a laser mouse with a built-in trackball for extremely fine pointer control? I'm visualizing your regular Logitech-style mouse with a smallish trackball embedded under the thumb. You'd be able to mouse normally with your wrist, but use your thumb alone for tiny motions. Seems like the best of both worlds, but I can't find evidence one has ever been sold? The closest I can find is this Kensington SlimBlade, which kind of toggles back and forth between regular and trackball mode. The Masked Booby (talk) 02:14, 17 May 2011 (UTC)

Are you sure your thumb makes finer tiny motions than multiple fingers dragging an object resting on Teflon pads? This is OR, but I just tried to imagine using the device you describe by moving my thumb around, and it's jerky as hell. In my individual experience, the combination of several of my fingers on my mouse seems to produce more accurate small motions. Comet Tuttle (talk) 16:49, 17 May 2011 (UTC)

I think the idea is that the sensitivity on the ball would be set so that even large movements of the ball only produce tiny pointer movements. I've never seen this done, either. I think I'd prefer separate horizontal and vertical wheels, which could either be configured to make fine horizontal and vertical movements of the pointer, say when trying to draw lines, or could be used to scroll vertically and horizontally, or could adjust brightness and contrast, or volume and right/left balance, etc., depending on the application. StuRat (talk) 16:59, 17 May 2011 (UTC)

If I might make a suggestion: I've found that extremely small mouses give one a huge amount more control over the pointer than larger ones do. I use an adorable little iHome optical notebook mouse (a whopping $15 or so). I got it as an extra, laptop-only mouse, but I use it exclusively now, whatever computer I'm on. I hold it in my fingers, not my palm — this is what allows me to have much more precision than with a regular mouse. It also needs a lot less desktop space than a full-sized mouse. Just putting that out there. --Mr.98 (talk) 17:53, 17 May 2011 (UTC)

This sort of idea is usually handled by mouse acceleration. If set properly, you move the mouse to the position on the screen you like. As you move there, it accelerates. Once in the general area, you stop moving the mouse. Then, you move it again and the pointer will move very slowly. If you overshoot the spot, you stop moving the mouse. When you start moving it again, the mouse will move very slowly again. By using short movements with pauses in between, you get extremely fine-tuned accuracy. By moving in one continuous movement, you can quickly shove the mouse across the entire screen. -- kainaw™ 18:49, 17 May 2011 (UTC)

I've had a similar problem with digital clocks that use one "time set" button with acceleration. They tend to be very difficult to adjust precisely. Different buttons going at different speeds (say one for hours and one for minutes) solves this problem, and might also solve it for a mouse, too. StuRat (talk) 20:36, 17 May 2011 (UTC)

I know that some mouse software will allow you to hold down a key to dramatically slow down the mouse. So you get your large movements and fine movements with the same mouse simply by holding down a key. I'm sorry that at the moment my Google skills aren't strong enough to find the drivers I'm thinking of, but I'm sure I've seen this before.

Actually, it looks like the SlimBlade uses the trackball as two-dimensional scroll wheel when not in mouse mode. It would certainly be theoretically possible to re-map that as fine mouse control, but I don't know if there are any existing drivers to do that. APL (talk) 17:48, 18 May 2011 (UTC)

What about a mouse that has buttons for instantly adjustable DPI instead? I've got the Logitech G5 which although isn't a new mouse now (but newer similar models exist) does this very quickly/easily with just one button press on either the extra up or down buttons. Although these mice are designed as gaming mice, it sounds like it has the feature that you want.  ZX81  ^talk 22:36, 18 May 2011 (UTC)

Junk computers

Hiya. I've got two computers that I have no use for myself, so I'm putting them to a good use and giving them away to a child welfare organization for education and entertainment purposes. The problem is that I don't have hard disk drives for these computers, and since the very point of giving stuff away for free is giving them away FOR FREE, I don't wish to cause unnecessary expenses to the receiving organization. As the computers are only needed to host a little space for files, some drawing and writing programs and a few games, even the cheapest HDDs of today seem oversized. So it would be swell if I could somehow have a HDD only on one computer, and have the other one use the same HDD for loading the OS and saving the files etc. Thanks! 212.68.15.66 (talk) 10:55, 17 May 2011 (UTC)

This doesn't answer the question but it may be useful to you; you could make a LiveCD for the computer without a hard drive. A LiveCD is an operating system which runs from a CD and doesn't need a hard drive to work. But anything people wanted to save like drawings or typing would have to be put onto a floppy disk or usb flash drive as you can't write to the LiveCD 82.43.89.63 (talk) 11:14, 17 May 2011 (UTC)

Hmm... an external USB-hard drive and a Live CD could be a feasible combination, whaddya think? And thanks for the great answer! =) 212.68.15.66 (talk) 11:18, 17 May 2011 (UTC)

It's perfectly possible to install Linux (depending on the old machines' capabilities, perhaps Puppy Linux) on a USB flash memory stick (which, with some deft wiring, you can locate safely within the machine's casing) and get a basic, reasonably performant machine that can do web browsing and email and stuff. But before you spend any time on this, I'd recommend you talk to the organisation you're intending to give the machine to. My experiences with trying to donate perfectly good machines (with a full complement of hardware) haven't been very successful - I've found:

• organisations don't want machines older than 2 or 3 years (they get so many offers of free machines they can pick and choose) and they're wary of businesses passing on old machines to them (as, if they don't use a machine, the organisation still has to pay a recycling fee)
• one organisation only wanted Windows XP (or above) machines; their volunteer technicians didn't know Linux, and they didn't want a machine with a blank disk (I imagine they didn't have a Windows site licence)
• some organisations didn't care what software is on the machine, as they just wiped it and put whatever they wanted on it

Every time I've tried to find a good home for a machine I was ready to donate, I found that no-one wanted it. -- Finlay McWalter ☻ Talk 11:39, 17 May 2011 (UTC)

Thanks for the tips, I've already contacted the organization and they're interested. I'm closely affiliated with the organization (over 5 years of volunteering, and I'm not even 20 yet!) and we've discussed getting some old computers for kids to play Solitaire and draw stuff with. Now the opportunity presented itself. I'm a computer hobbyist and am likely to find use for the machines myself if the organization, for some reason, decides not to take them. 212.68.15.66 (talk) 11:53, 17 May 2011 (UTC)

An anecdote... Beginning in 1993 and every year until 2008, I bought a new computer in September. I donated my old one to a needy family with a young promising student. They were always happy to get the computer - even though it was a year old. Then, in 2003, I added my name and phone number on the side of the computer to call me if they had troubles because I realized that they probably don't know what to do with a computer. Each year from 2003 to 2008, I got a call from someone other than the family I gave the computer to. The person who called me always said that they purchased the computer from a pawn shop just a few days after I gave the computer away. Five years of that and I quit giving my old computers away. I didn't even buy a whole new one anymore. Each year, I buy one rather expensive component such as a larger hard drive or better monitor or faster CPU. -- kainaw™ 12:24, 17 May 2011 (UTC)

Try Freecycle or your local equivalent for either obtaining old computer parts such as HDs after people upgrade, or for giving computers away. My computer is many years old and cost £50 second hand. Ebay could be another option. 92.15.1.9 (talk) 13:38, 17 May 2011 (UTC)

The organizations and computer recycling places that I have donated to (US) really don't care about the "whole computer" idea anyway. They accept the donated computers at their center or at special events, and then they are disassembled into their basic parts (drives, cards, power supplies) and tested. So they don't care whether a computer has 0,1,2 or 5 hard drives; they are going to be removed, tested, and then reassembled into computers to be provided to schools, charities, families, etc. This is desktops, I'm sure it's different with a laptop.--Romantic Mollusk (talk) 22:18, 17 May 2011 (UTC)

Tip, look for PXE network bootable machines. They won't need a harddisc of their own provided there's a network to connect it to some kind of fileserver. Electron9 (talk) 22:34, 18 May 2011 (UTC)

Redhat cluster suite alternative

I was reading an article discussing Redhat cluster suite and it made a reference to "popular alternatives". I searched for what those alternatives may be and I found recent articles referring to a Redhat cloud - which I don't think exists. I'm sure you can run a cloud on Redhat, but there isn't a specific Redhat cloud suite that I know of. Am I wrong? Is there a popular alternative to the Redhat cluster suite for general process load balancing (not just website traffic balancing)? -- kainaw™ 12:18, 17 May 2011 (UTC)

OpenMPI; Sun Grid Engine (now free and open-source software); Hadoop; Java Enterprise Edition (or OpenJDK). What sort of "general process load balancing" are you looking for? Do you intend to compile and execute a native binary program and parallelize by simply running the same program on multiple machines, or are you looking for coherency between the processes on each node? EJBs are probably your best bet if you intend to implement node-to-node parallel programming. If you prefer to code in C, you can write inter-node communication in MPI; or if you just want to "script" the execution, GridEngine fires off processes on each node and expects them to manage themselves (mostly). Hadoop allows you to write programs that run "in a cloud"; you simply register each server as an available Hadoop node. (See startup-wiki for the scripts to register nodes, particularly the slaves file). None of these "cloud" programs require Red Hat, or "Cluster Suite."

Regarding "Red Hat Cluster Suite", it looks like it's nothing more than some sample configuration scripts for Samba and maybe inetd; I don't see how it actually provides a "cloud," in the sense that the software above does. Information on "Cluster Suite" is sparse. I have generally concluded that "cloud" is a meaningless and useless term to describe "several computers" for marketing people who don't want to discuss actual implementation details (or even basic features and functionality). Nimur (talk) 14:08, 17 May 2011 (UTC)

Thanks. I don't think that any of those are specifically adopted by Redhat (yet). So, I think that by "alternatives", he is referring to the general Unix/Linux alternatives, not Redhat alternatives. I also suspect that the author of the article is heavily confused when it comes to what Redhat cluster suite is usually used for (failover protection for network services - not computing on demand or parallel computing), but that is an entirely different issue. -- kainaw™ 14:09, 17 May 2011 (UTC)

I believe that Red Hat's MRG is closer to what you're talking about with distributed computing. The Grid part of MRG is based on Condor, which is open source. If you're interested in RH's Cluster Suite, it is documented here. -- JSBillings 15:56, 17 May 2011 (UTC)

Asking a question at the Mozilla Thunderbird "Community" forum

Mozilla Thunderbird keeps doing weird unpredictable bad things to my Hotmail email account, such as deleting all my emails, downloading the same emails over and over again, not archiving recent Hotmail emails to my HD (which is the only reason I installed or use Thunderbird), and not archiving sent emails. I would like to ask some questions about how to stop this at the Mozilla Thunderbird Community forum.

After filling in the question box, I next had to register. Fair enough. But it wasnt simply registering with the forum - I was only offered options for using other accounts such as Facebook or a Google account. The only option I have is "Windows Live", which seems to be another way of describing the Hotmail account. It seemed to say that my account information will be shared. I wasnt able to find out from a help link what information will be shared.

My questions are 1) Will logging in via Hotmail/"Windows Live" mean that my email address will be visible on the forum? I get enough spam already. 2) Is there any simpler way of registering with the Mozilla Thunbderbird "Community" forum that does not require giving them any information apart from an email address? 3) Will they be given my private Hotmail account information such as my date of birth?

Nothing happened when I tried to register via "Windows Live"/Hotmail - I dont know why. The $64000 question is - are there any other programs which can download and back-up to HD Hotmail emails without requiring so much finessing? I have thousands of them and thus I cannot do them manually. Thanks 92.15.1.9 (talk) 13:30, 17 May 2011 (UTC)

Yes, you can use Microsoft Outlook to connect to Hotmail. It works incredibly flawlessly. The software is not free. Nimur (talk) 14:12, 17 May 2011 (UTC)

Thanks. My quibbles are that I deleted MS Office, which appears to include MS OUtlook, from my HD as I did not like it. I'm also intending to change over to Linux some day. 92.15.1.9 (talk) 14:29, 17 May 2011 (UTC)

Both Windows Mail (free with Windows - you've already got it) and Windows Live Mail (free with Windows Live Essentials - you've probably already got it) work well with Hotmail/Live/MSN mail accounts, and will archive everything for you. Personally, I use Thunderbird, and get everything from my WL (hotmail) account forwarded to a Gmail account which I use on Thunderbird. Works perfectly. I don't use a mail client on my Linux partition, so I can't help you with that part of your question. --KägeTorä - (影虎) (TALK) 12:29, 18 May 2011 (UTC)

Thanks, an older version of Windows Live Mail seems to work with WinXp, according to the article. Although someone could make $$$$ from writing a one-click email archiver. 92.29.112.23 (talk) 13:57, 20 May 2011 (UTC)

I've installed Windows Live Mail, and I'm pleased to say that you can tell it to save the emails on disk as .eml files, which Thunderbird can read. Regretably the file does not show either the email title or the date recieved, although these can be seen within the email itself. The email folders are 100 or 200 times bulkier than I expected, due to the text message that you see being only a tiny fraction of the whole email, and due to the program saving a lot of other very bulky material whose purpose is unknown to me. The emails are not archived and the program could delete them without asking permission, so a duplicate copy will need to be made to have an archive. I have not worked out if all the very extremely bulky non-eml files need to be archived as well, or what their purpose is. 92.24.186.11 (talk) 11:35, 21 May 2011 (UTC)

Once Windows Live Mail is installed and the emails are stored on the harddisk, then the freeware KLS Mail Backup can be used to archive them, although this could also be done by hand. Although I don't know how any of this deals with incremental back-ups. 92.24.190.64 (talk) 22:46, 21 May 2011 (UTC)

ACPI and sound when running Linux

With every linux distro I've used, I always have to add acpi=off to the kernel options in /boot/grub/menu.lst. However, in some laptops, the sound doesn't work with this option. How can ACPI have any relation to the sound card?

Many peripheral devices are integrated to save cost. I went looking for a good introduction to the economics of the semiconductor industry, but the best I could find was semiconductor consolidation. Suffice to say, costs are dramatically reduced (by orders of magnitude) when multiple features are integrated on to the same device; so, sometimes, seemingly unrelated features are actually managed by the same chip. Audio and power management actually seem logical (both are low-latency, small die-area devices) compared to some integrated features I've heard of.

If you know your motherboard manufacturer and model, we can help you find exactly what features are provided by each chip on the board; and determine whether this audio glitch is a "bug" or "known feature" as a side-effect of disabling ACPI. Nimur (talk) 21:09, 17 May 2011 (UTC)

Yes, in my present laptop it's a known issue. Quest09 (talk) 12:32, 18 May 2011 (UTC)

Google left navigation

Hi, like nearly everybody, I don't like igoogle's left navigation tabs (firefox 3.6.13). I have installed greasemonkey and a thing called "stylish" which worked for a bit (thanks!) but google have evidently installed some kind of update to spoil it again and now the left navigation tabs are back, unwanted as ever. Does anyone have any advice? I'm just going to have to move to netvibes or similar, the new igoogle is intolerable. Thanks, Robinh (talk) 20:28, 17 May 2011 (UTC)

http://kb.mozillazine.org/UserContent-example.css http://karmatics.com/aardvark/ ¦ Reisio (talk) 07:39, 18 May 2011 (UTC)

(OP) Hello Reiso, that's excellent! I managed to download and install aardvark, and it worked precisely as advertised. I can get rid of that stupid left hand navigation and then hit the 'Q' to exit aardvark. Do you have any idea how to do this *automatically*, each time I visit igoogle? Very best wishes, Robinh (talk) 08:40, 18 May 2011 (UTC)

(replying to self, after fiddling round with aardvark). I *think* I've figured it out. By installing R.I.P. ("Remove It Permanently", another firefox add-on), one can highlight the left navigation and hit the "K" key. And then it disappears! AFAICS, this seems to work perfectly. That is one big kia ora! Robinh (talk) 08:51, 18 May 2011 (UTC)

Was rather suggesting @-moz-document domain("www.google.com") { #leftnav { display: none !important; } } (or something like that) in userContent.css, but whatever floats yer boat. :) ¦ Reisio (talk) 10:23, 18 May 2011 (UTC)

I looked at the mozillazene webpage but didn't "get" it. I must be missing something basic. Presumably one cuts-and-pastes your code into a file somewhere and restarts firefox. What file is it? (macosx 10.5.8). Thanks again, Robinh (talk) 10:36, 18 May 2011 (UTC)

The link says what the file is and where it is (or should be). ¦ Reisio (talk) 11:24, 18 May 2011 (UTC)

Is it possible to have and use two or more editions of IE or othern browsers in one OS?

eg. could i download ie 9 without overwriting (not sure if this is the technical term) IE 7, and then choose the one want i want from the programs? what about OPs? can one have vista and win 7? --24.228.127.187 (talk) 23:32, 17 May 2011 (UTC)

IETester, VirtualBox 87.113.171.230 (talk) 23:51, 17 May 2011 (UTC)