Wikipedia:Reference desk/Archives/Computing/2007 November 5

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[edit] November 5

[edit] Buying a Computer Server..

I want to buy a server for holding a website.. live server (24/7).. in the range of $3,000 (a bit more or less, ok).. what's the best server for me?? thanx in advance.. Ahmad510 00:12, 5 November 2007 (UTC)

Apple offers one starting at USD 2,999.00 with free shipping. I do not recommend buying right away but try to see the configuration of the computer. [1] Maybe you could be adventurous and build your own computer by buying the parts. --Kushalt 01:41, 5 November 2007 (UTC)

Thank you Kushal.. but i need it to be compatible with Windows Server 2003.
Almost any new industry standard PC could run a server. Your specs will depend on what kind of load you expect - are there thousands of hits per second expected? Is there going to be input to the website? Are there terrabytes of data? Will much money be lost if the server is down? Graeme Bartlett 02:44, 5 November 2007 (UTC)
The server will be used for holding an online bookstore, i don't expect those "thousands of hits per second", no huge inputs or terrabytes of data.. and if the server is down, actually i'll feel so bad..
A bigger concern than the server itself would be other infrastructure it depends on. Do you have a backup power generator and redundant internet connections, for example? If you want reasonable reliability, you probably want to look at paying someone to host the site for you. Then, the server is their problem, not yours. Friday (talk) 20:15, 5 November 2007 (UTC)
You probably don't want to try to host a commercial web site over your home internet connection. Your options are to lease a server (or shared server) or co-locate your server. The former will be the most economical approach, although you will usually not have full control over your server. For co-location, you'll want to look at getting a rack-mount server (the Xserve is just one example of that, and while it can run Windows Server 2003, you'd be paying a premium for another operating system you're not using). A bit of searching will turn up some build-to-order options. Note that shared server hosting costs can range from as little as $10/month to as much as $150-200/month. The cheapest co-location I've found is $75/month for a 1U server. Donald Hosek 00:00, 6 November 2007 (UTC)
Are you sure they have PPC builds of Windows 2003? --ffroth 04:46, 6 November 2007 (UTC)
That's an Intel Xserve. Pinball22 04:52, 6 November 2007 (UTC)
Oh, I was thrown off by the language at the beginning of Xserve#Intel_Xserve: The Intel-based Xserves were announced at the... I didn't actually see that they were also released last year --ffroth 22:14, 9 November 2007 (UTC)

The idea of leasing a server isn't applicable at all for the owner of the website (I'm not that owner for sure).. and regarding the infrastructure, the server will be run using a high-speed DSL internet connection without a backup power generator or a redundant internet connections.. anyway such appendants will be handled later on if necessary.. Thanks for the contributers.

No sense buying a proper server if you're going to mom-and-pop it like that. Just use whatever you already have laying around. Also note that with most ISPs, hosting a server is a violation of the terms of service. So, they may stop it from working if they notice it. Also a potential problem is that you might not have a stable IP address, so people on the internet may not have a good way to reach your server. Friday (talk) 21:35, 9 November 2007 (UTC)

[edit] Recording Onto CD.

I was just wondering is there anyway I can record sound onto a CD using a 1/4" microphone jack? The same kind used with a kareoke or singers in concerts. Apparently it is possible but I have to get a CD recorder or use a computer for it.Jwking 02:14, 5 November 2007 (UTC)

You will need a microphone, which could have a plug to fit this size hole, then plug into your computers microphone socket on the sound card or mother board. Run a piece of software that can record. You then need a CD burner to make the CD. You can also by special CD recorders from a Hi Fi shop, but expect to pay considerably more than a PC for this. Graeme Bartlett 02:38, 5 November 2007 (UTC)
Or put another way: you don't burn directly to the CD from the microphone jack; it isn't like a cassette tape. What you do is record to your computer from the microphone (save it as a WAV or MP3 file, for example), and then burn the sound file to the CD with a CD burner (which can save it as an audio track so it will play in a CD player). You should use a computer for this, as it will already have most of the necessary components (mic jack, operating system, recording softwase) built into it. --24.147.86.187 15:39, 5 November 2007 (UTC)

[edit] "Total" row in PostgreSQL

I'd like to create a view that contains first the result of

SELECT "All Cards"."Rarity", sum("All Cards"."Non-foil"), sum("All Cards"."Foil"), sum("All Cards"."Total") FROM ("All Cards" JOIN "rarities" ON "All Cards"."Rarity" = "rarities"."value")
GROUP BY "All Cards"."Rarity", "rarities".sort_order
ORDER BY "rarities".sort_order

and then the result of

VALUES('Total', (SELECT sum("Non-foil") FROM "All Cards"), (SELECT sum("Foil") FROM "All Cards"), (SELECT sum("Total") FROM "All Cards"))

But I cannot simply join them with a UNION as long as the ORDER BY clause is present, because ORDER BY a non-result row is illegal (and generates an error message as such) when UNION is used. And if I drop the ORDER BY clause, Total isn't the last row and Uncommon isn't between Common and Rare. How can I define a view as the combination of these two queries, with the other rows in order and the Total row last, and without adding a superfluous column to contain sort_order? NeonMerlin 03:24, 5 November 2007 (UTC)

Well, since the "superfluous" column is such a problem, why not just next the first query in a select that would hide the sort_order and then union that with the second query? Personaly, I'd do this like (sorry, MySQL):

(SELECT a.rarity, sum(a.non-foil), sum(a.foil), sum(a.total), r.sort_order as so from 'all cards' as a inner join rarities as r on a.rarity = r.value GROUP BY a.rarity) UNION (SELECT 'Total', sum(a.non-foil), sum(a.foil), sum(a.total), '99' as so from "all cards" as a) ORDER BY so

Not sure about syntax errors, but the point is forget about superfluousness and set the sort order value of total to 99 or something big. Then, you can ORDER BY on the outside instead of from inside. When displaying the results to the user just dont display the sort_order field. — Shinhan < talk > 15:56, 9 November 2007 (UTC)

[edit] What's the on-screen arrow called?

It seems like "cursor" is used a lot, but does that really apply to GUIs? I think of the old blinking square. "Pointer" doesn't seem to be accurate either as it implies passivity (like a laser pointer -- it doesn't perform any actions). --24.249.108.133 06:41, 5 November 2007 (UTC)

I say "cursor" or "mouse pointer" or "mouse cursor". And I never even thought of it as an arrow until you pointed it out --ffroth 07:35, 5 November 2007 (UTC)
I would refer to it as the cursor or not use a noun and ask someone to "move the mouse to" or "mouse over". Also technically should we refer to it as an arrow head? It has very little shaft and no fletchings. It's more of a dart technically and don't forget you can change it from it's default to just about anything. Lanfear's Bane | t 10:27, 5 November 2007 (UTC)
It is officially a cursor, as Microsoft and Borland GUI development tools use that term in their components. It cannot be called an arrow as it could be changed to anything depending on your theme - even a dancing horse! Pointer is also acceptable as it always has a "hot spot" for you to click on items. Sandman30s 11:53, 5 November 2007 (UTC)
It is the cursor or the mouse pointer, and it has different states, one of which (the default) displays an arrow head. Others are the I-bar (for editing text), the compass-rose (for moving things around), the wait cursor (the hourglass), etc. Programmatically it is referred to most often as the Cursor and sometimes as the Mouse Pointer. --24.147.86.187 15:36, 5 November 2007 (UTC)
Even in DOS (or cmd) when it's just a flashing box or symbol it's still called a cursor. You can refer to the mouse cursor as the mouse cursor, there's a text cursor, etc. Rfwoolf 15:41, 5 November 2007 (UTC)
I prefer "pointer" to avoid ambiguity with the text cursor. I'd also be cautious about prepending "mouse" given the availability of other pointing devices. NeonMerlin 18:23, 5 November 2007 (UTC)
Eh, just because it's not used with a mouse doesn't mean it isn't clear. I use a trackpad (on a laptop) and if someone called it a "mouse pointer" I would know what they meant and would certainly not take any offense. --24.147.86.187 01:55, 6 November 2007 (UTC)
In formal writing, I'd use 'pointer' - but informally, 'cursor' works too. 'Arrow' doesn't work because sometimes it's an egg-timer or a cross-hair or something. SteveBaker 19:04, 5 November 2007 (UTC)
"Arrow" is also used for a number of keys on the keyboard ("arrow keys") and so you'd want to avoid any ambiguity there ("Click the button with the arrow" is ambiguous to me). --24.147.86.187 17:53, 6 November 2007 (UTC)

[edit] Making Windows 98 printer drivers work on XP

I've got a Lexmark 2050 colour printer running on an old Windows 98 machine. There is no driver for this printer for XP. The 98 driver doesn't work on XP and using the XP driver for closest model, the 2030, just gives garbled data. It's been an interesting problem and I've thought of a few things which might tax the brains of teh people here:

  1. Is there any way to get the printer and OS talking? I assume Virtual PC or VMWare would work but that is rather extreme. Nor do I want to dual-boot every time I want to print.
  2. Is there a Windows 98 emulator for XP out there anywhere? (Kinda like DOSBox.)
  3. Is there some sort of "wrapper driver" that can get the 98 driver talking to XP?
  4. How difficult are wrapper drivers to code? Or are they just impossible?
  5. What is so fundamentally different between the two OS's driver handling that XP cannot interpret the commands designed for a 98 driver?

Thanks for the help. Zunaid©® 10:46, 5 November 2007 (UTC)

There is Microsoft Virtual PC 2007, apparently free for download, which I believe you can use to emulate and install Windows 98 (if you have a copy of the CD, of course) on a virtual "partition" of your hard drive". There are emulators out there which allow you to "save the state" of a virtual machine so it doesn't require "booting" per print, although it might need a restart every now and then. I do think it's more extreme to start thinking about rewriting drivers to cooperate, because it's not easy and because these drivers operate at assembly code level or deeper (which explains why XP drivers may not work on 98, for example). x42bn6 Talk Mess 13:26, 5 November 2007 (UTC)

[edit] Recover photos from wonky flashcard

There's a popular piece of open-source software that helps rescue files from damaged flash cards; I just can't remember its name. I've seen it recommended on this page several times - can anyone remember its name? The Lunchbox of Dooom 13:18, 5 November 2007 (UTC)

PhotoRec and/or TestDisk. --LarryMac | Talk 14:44, 5 November 2007 (UTC)

[edit] Help with internet connection

My internet connection seems to "die" on my somtimes. I cant connect to any games on LIVE or be on aim and wikipedia at the same time. I have wireless internet thats unsecured could that be the problom? Also i have comcast Jack THE Pumpkin KING 17:36, 5 November 2007 (UTC)

Using unsecured wireless is a really bad idea - unless your home is at really good distance from where anyone else lives or works or parks their car. My 'weekend' home is like that - it's out in the woods, half a mile from the nearest other building and a quarter mile from the nearest road - so I don't bother to secure my WiFi. But my apartment here in Austin has maybe 100 active computer users within range of the transmitter, so it has the maximum level of protection enabled! I also had to be careful to tell my computer to use that WiFi connection point ONLY and not to pick up one of the half-dozen unsecured access points in the area! It's perfectly possible that enough other people are squatting on your signal to prevent you getting access - but it's also possible that your PC is latching on to someone elses unsecured access point. The way most people set up their computers, they may actually be trying to legitimately get to their own WiFi box - but because yours was auto-detected, they may be picking up a poor/overloaded signal from your WiFi box and using that instead of their own perfectly good one. You should secure it - immediately - and also make sure your PC and game machines are set up to ONLY access your box. SteveBaker 19:02, 5 November 2007 (UTC)

The problom is how do i secure it. i had my father try to but he said sometinh about a w12 code or someting like that. Jack THE Pumpkin KING 19:04, 5 November 2007 (UTC)

You're still using it and you haven't secured it? OK do this ASAP. Comcast gives some good advice- first turn off SSID broadcasting and change your network SSID. This makes it difficult for attackers to "tune in" to your network's wireless signal without knowing the name of the network. You'll have to manually set up each of your wireless computers to use that network ("Manually connect to a wireless network" or something like that for vista) because they won't autodetect it. Next enable WPA encryption- don't listen to Comcast on this point, they probably just want you to use WEP because they don't want to have to upgrade the ancient routers they lease out to customers. WEP has serious flaws to the point where it's barely better than no security at all. Finally if you want ultimate security, use static IP addresses (disable DHCP on your router) and only allow access to the MAC addresses of the computers that you want have the ability to connect the network with.. to.. --ffroth 22:14, 5 November 2007 (UTC)

[edit] Why do magnets render disks unredaable, and do they do the same w/DVDs?

A good friend told me his brother worked for a computer store, and one day a woman called and said her disks she bought were defective; here she'd stuck them to her refrigerator with magnets. (And you thought you heard 'em all about dumb things people do :-) My question is, first, why did magnets do that to disks, and second, are DVDs safe from those who would stick them someplace with magnets? I could see a magnet erasing a disk, but why would it render the disk inoperable?Somebody or his brother 19:32, 5 November 2007 (UTC)

Magnetic media can be disrupted by magnets. Optical media wouldn't be, unless the magnet happens to scratch it or something. Friday (talk) 19:34, 5 November 2007 (UTC)
Thanks - I hadn't really understood magnetic fields and such, but I'm understanding it now, after having read that and a couple other linked articles.Somebody or his brother 20:10, 5 November 2007 (UTC)
A magnet will not only erase the user's data from a magnetic disk but also the low-level formatting data. The disk can still be reused if it's reformatted, but this user might not have known how to format disks (most disks these days being sold preformatted). -- BenRG 22:21, 5 November 2007 (UTC)
Basically disks, as magnetic media, have their information inputted by a varying magnetic field which inputs the 1's and 0's as different magnetic fields. VHS and cassette tapes work the same way. CDs and DVDs instead have their data on them (still 1's and 0's) put in place by burning a little hold in the plastic of the disk with a laser. --01:57, 6 November 2007 (UTC) —Preceding unsigned comment added by 24.147.86.187 (talk)
CDs and DVDs don't have holes burned in them by lasers. CD-R and friends use a dye that changes its reflectivity when heated. Mass-produced discs are injection-molded (see compact disc manufacturing). Even mass-produced discs don't have actual grooves in them, just variations in the depths of internal layers. -- BenRG 19:27, 6 November 2007 (UTC)

[edit] Cellular/wireless "bars"

Is there an article specifically about the iconography that is commonly used in mobile phones to indicate the signal strength? What are they called? They look like a stylized representation of an antenna(?), and to the right of them there are up to five vertical bars of increasing height. They're currently used in Cingular's advertising, and the Sprint Nextel article says that Nextel used it in the past in their advertising and that the current logo is derived from it. —Random832 19:48, 5 November 2007 (UTC)

The Y-shaped icon is a universal electronic symbol for antenna. The bars, however, don't actually mean anything. They are subjective, similar to an S meter. --Mdwyer 20:26, 5 November 2007 (UTC)
Mdwyer is correct. If you move your phone and the number of bars increases, the strength of the signal between the phone and the Cell site it is connected to also increases. However, the number of bars displayed for a given absolute signal strength differs between Cellular networks. The voice quality of any particular call does not necessarily correlate with the number of bars, but in general, the more bars displayed, the more reliable the connection and the clearer the voice quality will be.Thomprod 22:24, 5 November 2007 (UTC)
its not correct to say they mean nothing. They are the signal strength in db relative to the background noise. The reason that people say they 'mean nothing' is that signal strength has little to do with quality of reception for digital spectrum sharing. You drop out and get no signal when there is simply no frequencies available to transmit on or people are transmitting over you. —Preceding unsigned comment added by Dacium (talkcontribs) 06:37, 6 November 2007 (UTC)