Wikipedia:Reference desk/Archives/Computing/2007 March 14

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March 14

smd vs. through-hole

In the case of a varistor, how do its paramaters such as maximum energy and maximum continuous voltage vary when you convert a through hole varistor to an SMD? thank you.Gfranz G 03:03, 14 March 2007 (UTC)Gfranz

Moved to Science desk. --Ouro (blah blah) 07:12, 14 March 2007 (UTC)

Thanks for taking the time in answering my question but I guess I didnt communicate my ideas well. What i meant by "converting" is to look for an SMD equivalent of a present through-hole varistor. In my case, the maximum continuous voltage of my through-hole varistor is 275Vdc and its maximum energy is 104J. I've looked up to the internet looking for SMD Varistors with the same or even almost equivalent parameters but the maximum contiuous vaoltage that I saw was around 56Vdc and worse for the maximum energy, the highest value that I got was 1.5J. that is why I was thinking that maybe some of the parameters of a varistor would be changed when it is "converted" from through-hole to SMD.

Why not mount your thro hole version in an SMD fashion (ie with short leads) You could glue the body to the board B4 soldering!?

Microsoft

about strenght of microsoft,weakness,opportunity,threats of microsoft

See Microsoft and related articles. --Ouro (blah blah) 07:12, 14 March 2007 (UTC)

I like this one :) --froth^t 07:57, 14 March 2007 (UTC)

I was thinking of linking related articles directly to the one you suggested ;) --Ouro (blah blah) 08:16, 14 March 2007 (UTC)

Authorization Management Program

Dear all,

I would like to finish my project about wireless authentication and authorization management as soon as possible. I spent already 2 years with many people in studying how to let my program work and trying to finish it, but it never break through.

My program functions as

1. Server: force all computers that can see and join the network and getting IP from DHCP cannot communicate with anyone else until one can pass the authentication and authorization process.

2. Server: the network catagorize the computers from inside/outside the group. (Done)

3. Client: user has to put the username and password to get the permission. (Done)

4. Server: give the permission according to the group, user, and time.

Now my program can catagorize the machine in the network and outside the network by using MAC Filtering and can authen the username+password, but cannot block or give the permission according to the requirements.

Actually, i have one CPP code that can block and unblock by hooking to the windows kernel, but i don't know how to pack this code onto my VB interface, and i don't know how to make it allow different policies to different groups.

If you have any idea, please suggest me a.s.a.p. Or if you want to try my code, i gonna give it all to you.

Littlepu 06:18, 14 March 2007 (UTC)

Please do not post the same things twice. Thank you. --Ouro (blah blah) 07:04, 14 March 2007 (UTC)

Why would you need special code on the client at all? Just refuse to give the connecting computer an IP address if it can't pass authentication. Have a little app on the client that asks for the username and password and sends it to the server. If it checks out, then allow the client to connect. Am I missing something? Are you supposed to rewrite the entire network adapter? And what does any of this have to do with wifi? One thing is for sure- it's a very bad idea to try to block access by hooking the client's kernel.. he has more control over his computer than you do and it's going to be impossible to enforce such a block --froth^t 07:53, 14 March 2007 (UTC)

So do you think what i should do with this program? I really have no idea. I have to finish it a.s.a.p to get my degree. But now i just want to code on how the give the permission according to the group, user, and time. Could you suggest me some idea? Thanks. Littlepu 06:58, 20 March 2007 (UTC)

Video card woes, why won't this silly computer let me use a PCI card with this dual-head AGP card?

Hi, Wikipedia Reference Desk. I just found you today. I was going to use Google Answers, but of course, the one time i'd actually need it to ask a question, it's gone.

I have a problem, but first i'll drop the hardware specifications.

MSI K8T Master2 FAR
Dual AMD Opteron 1.8GHz
2x 1GB DDR/3200
ATI Radeon 7500 AGP
2x 250GB SATA, 4x 9.1gb SCSI-2
Windows XP Professional, Solaris 10
DC390-F SCSI, 3Com 509B

I've got two 21" CRT monitors hooked up to my Radeon 7500, one's using the DB15 monitor port and the other's connected to a HDMI->DB15 adapter on the HDMI port. I want to add a third monitor to increase my productivity and let me produce far more TPS reports per hour.

I've plunked in a myriad of PCI video cards that are all known working and for some reason, they won't work. They install fine, Windows XP finds and installs all the drivers and they show up as a usable device in the Device Manager. I can't, however, extend a desktop on to it. In Display Properties -> Settings, it still only shows two adapters. No matter what I try, I can't get any PCI video card to actually drive a monitor. If I take out the Radeon AGP card and put three PCI video cards in, it works just fine. This, however, is unacceptable unless I invest in three decent PCI video cards, which is only a last resort.

Oh, magic eight ball, won't this work?

Any ideas, Wikicommunity?

Love, Wikijimmy

Sorry this isn't much of an answer but I tried to do this once, ages ago, and I came to the conclusion that it couldn't work. I'm pretty sure that I read somewhere that AGP uses the same video interrupt or something as PCI and you can not use both at the same time. Sorry I can't remember where I read that.. Vespine 00:32, 15 March 2007 (UTC)

It's possible. I bought a second screen some 2-3 years ago and wanted to have a dual screen setup. I had no problems to set up an old PCI card (4MB, S3 Virge chipset) along with my Nvidia GeForce 4 temporarily until I could get a new card supporting two screens. --Dapeteばか 14:07, 15 March 2007 (UTC)

Accesing Server Accounts

Hi, i would like to know how to gain access to server accounts. In my school each of us have a separate account on the main server thus each of us has our own different account on which we can log on from any system in school. What if i want to have access to another account which is password protected or can i see its contents somehow witout having to open it? do i have to synchronize it or something? if so how? —The preceding unsigned comment was added by 61.95.191.49 (talk) 11:22, 14 March 2007 (UTC).

Are you talking about getting unauthorised access to someone else's account on your school's server? That's very probably a violation of your school's network usage rules and could get you in trouble. Passwords are there for a reason.

If you're talking about doing it for a legitimate reason, like sharing a document with someone, it's probably easiest just to send it over email (or share it with them on Google Documents). Your school may also have shared folders where you can put files and let other people access them. Talk to your IT helpdesk and see if they have something like this set up. — Matt Eason ^{(Talk • Contribs)} 11:41, 14 March 2007 (UTC)

Can't remove history

In my local configuration folder there's the History one, but... it is read-only, I can uncheck that checkbox but after I open the folder again I see the tick has come back. The IE button clear history won't do anything. —The preceding unsigned comment was added by 85.50.148.87 (talk) 12:44, 14 March 2007 (UTC).

click on the start button, then run. next type in regedit. a screen will come up and on this screen go to HKEY_CURRENT_USER → Software → Microsoft → Internet Explorer. then go to typed urls. finnaly delete any urls you want. (make sure you dont do anything else in the registry. this should work. [1] --jake 01:21, 16 March 2007 (UTC)

Apart from what the above poster said, maybe your problem has something with that autocompleting function Windows has, that sometimes acts the same as the Internet Explorer history. To disable it, go to Control Panel, Internet Options, Content. There you have it, hope that helps. --Taraborn 10:17, 15 March 2007 (UTC)

Midi Issues

I have a Dell 9300 laptop with a boring SigmaTel sound card. I was trying to learn to play something on the piano before, using my laptop to guide me when I realized that something was out of tune. For a few minutes I thought that every key on my piano was half a step too high. Then I realized that the midi output on my laptop that is half about step too low. I compared it to the midi output on my desktop, which is in tune with my piano. I tested my headphones to make sure it wasn't just the main speakers. Same problem. Any thoughts? It just seems to be the midi and no other sound. --Russoc4 15:58, 15 March 2007 (UTC)

Are you using the Sigma driver or the Microsoft Midi emulator? I have not had a problem with the MS mapper and it has amazingly rich vibrant samples for a MS product... Sandman30s 07:59, 15 March 2007 (UTC)

Microsoft GS Wavetable Sw Synth. It doesn't let me pick anything else. I figure a reformat and reinstallation of windows would fix the problem. It fixes everything, but I was hoping there would be an easier way. Should I try uninstalling/reinstalling the sigmatel driver, even if it doesn't use it for midi?--Russoc4 15:58, 15 March 2007 (UTC)

give vim its own $HOME on windows

Is there a way on windows using gvim 70 to get vim to use a $HOME directory other than the "normal" one that windows uses by default? (e.g., c:/documents and settings/users/blahblah/NoClutter"). I would much rather use "c:/docs/MyHome" or something like that instead. Any :help or links that talk about this? NoClutter 16:13, 14 March 2007 (UTC)

Sure. Set the HOME environment variable to the directory it should use in My Computer | Properties | Advanced | Environment variables. —EncMstr 16:46, 14 March 2007 (UTC)

Ok thanks, just to double-check, this won't have the side-effect of changing the "default" that gets used by windows will it? This will only affect Vim right? I ask because the main reason I want to avoid using the windows path is: 1) the ugly spaces in the path, but also; 2) the fact that windows apps tend to put a lot of *crap* in there that I never use and don't ever want to look at. So I want to keep vim nice and clean, and separate. TYMV. NoClutter 16:57, 14 March 2007 (UTC)

It's fine. Most Microsoft programs don't know about it and don't care, being registry-focused instead. Only a few MS programs use environment variables; I don't recall any which use HOME. Other unix-based programs will use it of course, but they are probably doing what you expect: looking for .rc files and the like. —EncMstr 17:07, 14 March 2007 (UTC)

Moved from trancluded page

Setting up a network

OK let me ask the original question in a new way. I have a Computer running XP (this one) and a slow computer (200Mhz) running Win 98 SE. I wish to use the slow m/c as a server (data storage device). i use to have it working, but since various fiddling with the slow m/c it has now stopped recognising the network. i have tried reinstalling the network software etc a number of times- no luck. Any suggestions on what I may be forgetting to do?--SlipperyHippo 05:18, 14 March 2007 (UTC)

Are both computers in the same workgroup? →Ollie (talk • contribs) 00:18, 15 March 2007 (UTC)

Yes I checked that!--SlipperyHippo 00:30, 15 March 2007 (UTC)

Check the firewall settings. When trying to get the computers to network and see eachother in the beginning, I would completely disable both firewalls (disconnect from the internet if necessary and unplug your internet access if you really have to) -- and I mean disable both your Windows Firewall (XP) and your antivirus or firewall software. That is one of the most common networking solutions.
Then I assume you know how to ping different IP addresses on the network. This is useful if you want to see if your computer can see the other computer, even though it might not be able to connect to it yet.
Good luck, and remember, in order to help you it may be advisable to provide as much information as possible, such as operating systems, the method of networking, what kind of ethernet connection or hub or router, do they have network cards, what network software do you mean, what firewalls do you have, etc. Rfwoolf 11:42, 18 March 2007 (UTC)

Servers v external large Hard drives mainly for data storage

What are the comparative advantages/disadvantages (apart from price) of dedicated servers (espthe new HP device soon to come out running Microsoft Server softwware) over just attaching, say, a 300G ext HDD to my current 2.3 GHz computer. Thanks--SlipperyHippo 20:26, 14 March 2007 (UTC)

Are you referring to NAS when you talk about servers? Johnnykimble 21:22, 14 March 2007 (UTC)

No i dont think so. Thats the first I ve heard of NAS! I was talking about this new thing thats coming out Q2 this year made by HP (or another computer configured as a server). My 'network' will be my (DELL)workstation and my 'server' only--SlipperyHippo 22:11, 14 March 2007 (UTC)

In that case then, unless you do have gigabit Ethernet and given it is only you and 'it' on the network, I'd go for an external USB Hi-speed drive instead. As GB mentioned, your expansion options are enhanced with a server, but if you're going to be accessing it a lot, you should see benefits of the much faster connection via USB. Johnnykimble 22:27, 14 March 2007 (UTC)

No I dont have GB ethernet (only 100Mbps LAN cards). THank you for your advice (its cheaper too!)--SlipperyHippo 22:54, 14 March 2007 (UTC)

With an external disk server you have a lot of growth capacity - you can add many of the boxes to get a huge amount of storage. The servers can be easily shared between many users, and will have more reliability and up time than an average home PC. You PC will not have capacity to plug in many disks. If you have a gigabit ethernet on your PC and server you can get high throughput, comparable to USB connected drive.

Disadvantage will be more boxes to turn on or go wrong when the power fails, more noise and heat output, more complex to set up, more space and power points required. (A USB drive may need a powerpoint too) GB 21:32, 14 March 2007 (UTC) I don't know anything about the new HP drive. GB 21:32, 14 March 2007 (UTC)

Wouldn't gigabit Ethernet offer a theoretical doubling of throughput versus the USB drive? I think though if the spec of the data storage server is the same as the one mentioned in SlipperyHippo's previous question, achieving this might be difficult. Johnnykimble 22:15, 14 March 2007 (UTC)

Theoretically, yes. In practice, a hard drive is not fast enough to saturate either a USB2 or GigE connection in sustained transfer. --Carnildo 23:07, 14 March 2007 (UTC)

A SCSI drive could in practice saturate it though couldn't it? Although this is probably way beyond what SlipperyHippo had in mind for a data storage server. Johnnykimble 23:13, 14 March 2007 (UTC)

Yes: the other thing I should have said is that I have a large amount of data (~ 10G ) on my other drives in the non working 'server' at present and I would really like to make this data accesible to my workstation again somehow in whatever new configuration I choose. Thats why I was interested in the new HP server system (which I cannot find the link to at present). On that system I believe you can plug in any old drives and they become available on your 'network'. --SlipperyHippo 23:49, 14 March 2007 (UTC)

SCSI's no different: sustained transfer rate is limited by the mechanical design of the hard drive. Now, a RAID 0 array could saturate the connection, or a RAID 1 array with the correct access pattern, but no single hard drive is fast enough to. --Carnildo 21:05, 15 March 2007 (UTC)

very old CD

I have a CD labelled Sega Megadrive Emulator For Windows 95 98 3.1 Dos, and a Windows XP computer. Is there anything I can do to get the CD to do whatever it does on my computer, and what does it actually do?HS7

The emulator is basically a program to mimic the functionality of a Sega Megadrive games console on your PC. Crucially, you need games to play on it. These are in the form of ROMs and are usually illegal to download. You could try installing it using the Windows XP Compatability mode (right click the installer\setup.exe then select 'Properties' then go onto the 'Compatability' tab), but I haven't had much luck with this feature myself. Take a look at the article on console emulators for a more detailed explanation of what it actually does and the legal issues surrounding ROMs. Johnnykimble 21:43, 14 March 2007 (UTC)

You can also get many old DOS programs working on XP with DOSBox.[2] Shui9 22:02, 14 March 2007 (UTC)

If you want an emulator which will run on your current system, there are a batch to choose from--the functionality on that CD is available in plenty of freely-available programs. Of course, if it has ROMs on it, those are more difficult to acquire (not to mention usually illegal), and you'd want to get those off the CD. grendel|khan 14:28, 21 March 2007 (UTC)

IE 6

How do I reset all my web settings and history on IE 6? 68.193.147.179 22:10, 14 March 2007 (UTC)

Tools -> Internet Options -> Clear History. Splintercellguy 23:13, 14 March 2007 (UTC)

Office 2003 Trial

Where can I get a Office 2003 Trial? 68.193.147.179 22:11, 14 March 2007 (UTC)

I don't believe there is a trial, though I could be wrong. If there is one, Microsoft.com.Splintercellguy 23:13, 14 March 2007 (UTC)

Here you go. --froth^t 23:14, 14 March 2007 (UTC)