Wikipedia:Reference desk/Archives/Computing/2006 July 21

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Microprocessor

How does the microprocessor 8089C-51ED-2 work and where can I find the information related to it on the net? --K.C.Priyanka 02:59, 21 July 2006 (UTC)

I repaired the question so easier for people to read it User:AlMac|^(talk) 05:01, 21 July 2006 (UTC)

I am not an expert on this aspect of computer technology, but I did skim over the Wikpedia article on microprocessor and saw numbers right around the 8089 but not dead on. Looks to me like it might be made by Intel so perhaps their web site http://www.intel.com/ might be a place to check. User:AlMac|^(talk) 05:09, 21 July 2006 (UTC)

You can find a lot of information on the Internet by using search engines, such as this way http://www.google.com/search?hl=en&lr=&q=8089C&btnG=Search User:AlMac|^(talk) 05:04, 21 July 2006 (UTC)

It appears to have been an Intel chip c. 1982 that was used mainly as an Input/Output co-processor. The Intel website doesn't seem to cover it though. Robmods 12:57, 21 July 2006 (UTC)

System requirements

I could swear that once someone told me how to see information on memory, graphics cards etc. in a way that was useful to compare to system requirements lists on computer games. It's not under Help and Support or My Computer, as far as I can tell. Help plz? Vitriol 17:25, 21 July 2006 (UTC)

You mean to see the stats of your own computer? On Windows XP: to see your processor and RAM stats, right click on My Computer and select "properties", and it will be there. For other more detailed stuff, including Graphics cards, sound cards, disk drives, etc, right click on My Computer, select "Manage", and then from the list on the left column of the screen that pops up, select "Device manager". If you need more help than that just ask. —Mets501 (talk) 17:29, 21 July 2006 (UTC)

I'm sure it was easier than that. Vitriol 17:38, 21 July 2006 (UTC)

If you have directx installed, you can go start->run->dxdiag and get a lot of information, though perhaps not what you're looking for. Digfarenough 19:13, 21 July 2006 (UTC)

Wow, that's cool! I didn't know about that! —Mets501 (talk) 19:18, 21 July 2006 (UTC)

Since you don't specify what operating system you are using, you probably don't realize that the question exists, which means you are using some version of Microsoft Windows. In that case, some freely downloadable utilities are SiSoftware's Sandra, Lavalys EVEREST (though support has been discontinued), CPUID's PC Wizard 2006, and Belarc Advisor (which generates a summary). --KSmrq^T 20:27, 21 July 2006 (UTC)

It's too late, Digfarenough got it. I remember now. :D Vitriol 20:56, 21 July 2006 (UTC)

Software utilities such as Everest or the abovementioned software are sometimes easier to use and contain more information. CPU-Z is also useful. --Proficient 23:10, 21 July 2006 (UTC)

Code library conversion

I've got a code library (a .lib file) compiled with Microsoft Visual C++. How do I use it with the Windows version of GCC? Do I need a converter? --67.185.172.158 17:32, 21 July 2006 (UTC)

This may be what you're after. EVOCATIVEINTRIGUE TALKTOME | EMAILME | IMPROVEME 17:34, 21 July 2006 (UTC)

Python: Setting a "global" variable with a function.

Any variable used within a function is strictly local: as I understand it, it cannot be used / doesn't exist in the rest of the program. This is proving to make a lot of code repetative in the programs I'm writing, so a method to get around this is what I'm looking for.

I've tried something like this:

  variable = myFunction()

This puts the result of myFunction as the value of the variable. However, this method can only be used for one variable. I was thinking of perhaps returning the values of the function as a concatenated string.. i.e. if myFunction had five values (01, 02, 03, 04 and 05) I wanted to be variables, it returns the string:

  0102030405

I would then set something like:

  variable = myFunction()
  a = variable[0:2]
  b = variable[2:4]
  c = variable[4:6]
  d = variable[6:8]
  e = variable[8:10]

This seems to be a very clumsy solution though; perhaps there is a more elegant solution?

I'm very new at programming, and am following an online guide to learning the language from scratch. I've tried looking in the index of the guide I'm reading and couldn't find anything, and I also tried searching Google but with no luck.. Any help would be much appreciated.

P.S. It just occurred to me that the variables above (a,b,c,d,e) are strings, I know I'd have to convert them to integers to be able to use them, so there's no need to correct me on that.

If myfunction returns a 5-tuple (constructed like (1, 2, 3, 4, 5)), you can unpack it like

a, b, c, d, e = myfunction()

instead of that ugly, overflow-prone string encoding method. When multiple values are required to be returned, a tuple is your best bet. --Sam Pointon 20:20, 21 July 2006 (UTC)

I've never encountered the word tuple before. So thanks for that, now I have something to search for so I probably won't have a problem finding the rest out for myself. Thanks again!

In Python, you can access a global variable inside a function by declaring the variable to be global, using the keyword "global". Example:

   def f():
       global v
       v = 1
   
   v = 0
   f()

After executing the above code, global variable v will be set to 1.--68.238.246.143 02:38, 22 July 2006 (UTC)

I'd just like to note that the above, global-modify code, is bad style. global statements should be used very sparingly (ideally, none at all). If a function needs mutable state, use a class:

class Foo(object):
    def __init__(self):
         self.v = 0

    def f(self):
         self.v = 1

foo = Foo()
f.f()

After that block of code, foo.v is set to 1. --Sam Pointon 10:29, 22 July 2006 (UTC)

eMule

My computer crashed a few minutes ago. This caused me to lose connection to the eMule server I was connected to and now I get connected to another one which doesn't have any of the files I was downloading. How do I see which server I need to connect to? There's too many to choose from. Is there some sort of server connection log? = Mgm|^(talk) 22:01, 21 July 2006 (UTC)

• Follow-up: The new server says I have a LowID. How do I get a HighID again? Did I ever have one. Speeds seem to be down in general. - Mgm|^(talk) 22:40, 21 July 2006 (UTC)

Try reestablishing the connection again. Check to see that you have your [ports forwarded|port forwaring]. Make sure that your firewall is allowing you to use eMule. Did you do any upgrades to any programs? Try to turn off your modem and try again. --Proficient 23:11, 21 July 2006 (UTC)

• Somehow I got it working again. Thanks for trying. My firewall (if I have one) allowed me to use eMule so far, so I see no reason for it to not work now. I had the crash when I was playing a video file, no upgrades, and I don't use a modem -- that's too slow a connection. - Mgm|^(talk) 08:19, 22 July 2006 (UTC)

'turn off your modem and try again'??? I mean come on! Anyway, edonkey servers are linked together, it does not matter which you connect to with respect to file availability. It does, however, matter that you get a High ID in order to get files from certain sources (namely people with LowIDs). This is where proper port configuration on your firewall is important. --Jmeden2000 15:24, 24 July 2006 (UTC)

Very noisy computer

I want to quieten my very noisy computer. It has two fans - one on the CPU, another on the box.

I think the CPU fan will be impractical to replace as they are attched in a special way to the CPU.

Can anyone tell me what proportion of the total noise do the two fans usually make? In other words, is it worth just replacing the box fan. Will this make any difference?

I would be grateful if anyone could also tell me a) how to identify the exact fan I need, and b) where to buy a quiet fan, preferably by mail-order in the UK?

Thanks. --62.253.52.139 22:35, 21 July 2006 (UTC)

You can replace both fans. I am going to assume you don't know what a CPU looks like - please don't be offended if you do. The CPU is a very thin little chip on the motherboard. It has a large heat sink mounted to the back of it. It clips around the chip and has a lot of (usually white) goop to help transfer heat from the chip to the heat sink. The fan is attached to the heat sink, not the chip. So, you will need to replace the whole heat sink - there are some very quiet ones and some that have no fan at all. As for the case fan, you can get quiet ones too. Check your power supply, that usually has the loudest fan. Then, look at your BIOS. You may have the option to throttle the fan with the CPU's core temperature. That makes a huge difference because the fans run slower when it is cool and then get loud only when it is hot. --Kainaw ^(talk) 00:12, 22 July 2006 (UTC)

As you said yourself, replacing the CPU fan means messing with the 'goop' attached to the CPU - I don't think I want to do this. I only saw this fan and another one at the back of the case when I had it open some time ago - is there another one also?

What you said about the fan throtteling to the CPU temperature is interesting. However I doubt my cheap and old computer can do this - I've explored the various settings on my computer over the years, and I've never come across it. But when I've tried to use free software to measure the CPU temperature, it either gives no reading at all, or it gives a 'meltdown' temperature. My computer has been working OK for months or years since then, so I am sure this is a mistake.

I would be very grateful for any help in identifying the particular fan I need. Thanks again.

There is no such thing as a particular fan. There should be at least 3 fans in any modern computer: One inside the power supply, one inside the case, and one on the CPU. As for the goop on the CPU, new heat sinks come with a tube of goop to replace it. As for the fan in the case and power supply, they are most likely standard 3-inch fans. Those are sold all over - you can go to Radio Shack if you can't find a computer store. There isn't a lot of technology in the basic fan world. The difference is the bearings that hold the fan in place. The quieter the bearings, the quieter the fan. Also, make sure there isn't anything in the fan - like cables, old post-it notes, dead animals... You wouldn't believe what I've pulled out of old computers. --Kainaw ^(talk) 21:31, 22 July 2006 (UTC)

You might be interested in Silent PC Review; they have lots of info, though they border on the obsessive. For your purposes, it would be helpful to know the dimensions of your fans, and what era your computer hails from. - mako 08:14, 23 July 2006 (UTC)

Thank you for the link to the Silent PC Review, I have been reading their fax. It mentions and evaluates various brands of fan, and gives a UK on-line supplier which sells fans, both good and bad.

I do not know what the size of case fan is without opening the case and measuring it. I have a etower 566cd, from about 2001. Although the computer I saw in the shop was silent, my computer has been very noisy from day one. Thanks.

Most modern motherboards have temperature sensors that make fans run faster as temperature increases. Therefore, your PC might be running a little hot. Probably the most common cause of this is dust building up inside. Go and buy a can or two of compressed air, open up your PC's case and blast it all out. Make sure to get it all off the heatsinks and fan blades too. Use a bit of masking tape or something to stop the fans turning, so you don't damage the motors (something I've heard can happen). I wouldn't recommend blowing it all out yourself, as you end up tired, not much dust shifted and a motherboard doused in saliva. DO NOT take a vacuum cleaner near the inside of your PC, as the static electricity from it can damage chips, although you might want one on hand to deal with the inevitable cloud of dust. I've seen my processer temperature drop by 10C after a good cleaning, and by extension, the fans quieting down. CaptainVindaloo ^{t c e} 17:50, 23 July 2006 (UTC)

I did try to buy some compressed air once. In the back-street computer shop I went into I was offered a tin can of something that looked like it was a spray for cleaning keyboards or the outside of cases. It did not mention "compressed air" on itself anywhere. It had a lot of liquid in it, and when I queried this the shop assistant said that that was liquified air! (What a moron!). I did not buy it. So is "compressed air" really compressed air, or is it just some sort of volatile liquid/gas? Thanks.

Compressed air is simply normal air stored under high pressure, which means it will blast out when you open the can. Robmods 21:10, 26 July 2006 (UTC)

I've heard of a new technology for computer cooling that is completely silent, and it gathers no dust. It works through a liquid-cooling system that surrounds the inside parts of the computer that normally get hot. It pumps cold water through plastic bags inside the computer.--epf 21:55, 26 July 2006 (UTC)

One possible source for "fan noise" is a ribbon cable touching the moving fan blades. Remove the outer case from the computer and boot it, to determine the source of the sound. If it is a ribbon cable, just secure it so it doesn't hang into the fan any more. A twist-tie might do the trick. StuRat 00:16, 27 July 2006 (UTC)

Problems with Remote Desktop Connection through my Router

This problem seems ridiculously easy, but I can't figure it out. I have a Linksys Wireless-G broadband router (WRT54G Version 4) directly connected to my computer (the other two family computers connect to the internet wirelessly while this one is hardwired). I can't seem to connect to my computer with Windows XP's Remote Desktop Connection from other computers; it won't resolve my IP address. Any suggestions? Thanks! --Samesong 23:08, 21 July 2006 (UTC)--Samesong 23:08, 21 July 2006 (UTC)

Did you enable incoming remote desktop connections on your computer? --Kainaw ^(talk) 00:13, 22 July 2006 (UTC)

I found this: http://www.microsoft.com/windowsxp/using/networking/expert/northrup_03may16.mspx

This works perfectly :D