Ok, so I noticed lately that more and more people complain about them having a high-speed connection but are seeing very low speeds in Limewire. I personally think that it's mostly due to people not having configured the application very well (if at all), mostly because that was my case too, so I decided to post in a new thread the few pointers that I followed when configuring my Limewire. Here they are:

a) First, make sure to know exactly what connection speeds you have, both upload and download. This may sound dumb but there are people who don't know (or maybe can't remember) what connection they are paying for. As a proof, many write in posts things like: "I have cable" or "I have a DSL connection".
While that's all good, you must know that there are different kinds of speeds, so knowing what connection speed you're on is more important (in this particular case at least).
Also, consider that DSL and Cable connection speeds are affected by the physical distance from the server, so if you have like a thousand kilobit connection but the server is, like, a zillion kilometers away (I obviously like exageration, huh?), then your speeds would still be incredibly slow.

b) Very, very important is also knowing the difference between bits and Bytes. When ISPs advertise their net connections, they use the data communications' measuring "system": the bit. You'll see things like: "1000 kilobits per second (kbps) connection available from, blah blah...". In data storage (includes most p2p filesharing apps I've seen so far) though, the Byte unit is used. The difference, which had me fooled at first, is that a Byte is 8 bits, which makes a 1024kbps DSL connection (like, say, mine) being able to (theoretically) run with 128 KBps speed (actually, it's 1000KBps as Morgwen points out later. You can go here to make a more accurate bit-to-byte-conversion). Don't misunderstand though: this is still pretty fast.

c) Now that you know a couple of things about your connection, it's time to get to configuring. The first step is to launch Limewire (duh). With Limewire launched, a Windoze user must go to Tools->Options while an OSX user will click Limewire->Preferences (for OS9 I heard it's Limewire->Options)
On the list to the left of the Preferences/Options window, click on Uploads, then Basic. If you know your upload speed (which you should), then drag the Upload Bandwidth meter so that it matches it. Done? Good. Now drag it down a little more, around -5 or so of your Upload bandwidth. Trust me. Just do it.

d) Now click Slots. I've personally set the uploads per person to 3, but anyway: the max upload slots should be decreased a bit as if you don't have enough bandwidth to satisfy all the demands, you'll end up queueing a lot of people and probably wasting your own bandwidth too.

e) Click Speed and make sure you've set the right speed (don't do things like setting it to T1 while you're on modem: it won't make you any faster).

f) Now for the good stuff: this will make you feel more like you're really fine tuning Limewire for better performance (despite the fact that the rest is probably just as important). Click Downloads. See the "Maximum number of simultaneous downloads"? You're gonna have to play around with that a little.
I don't know about others, but I thought at first that this was the number of active downloads (meaning the number of download slots in the "Downloads" window) I could have up at the same time. Well, it's not. This number determines the maximum amount of downloads you can have at the same time, but regardless of wether it's for the same file or not.
So, if you're on a broad-band connection, increase this number a little. Be careful: a little is really a little, meaning that you must increase this number by 1 or maybe 2. Increasing it too much (i.e directly setting this to 100) can have the opposite effect, as your Limewire will try to connect to more hosts than your bandwidth can handle. What you have to do is find a popular file (read: "a file with many sources") and download that. Remember the speed you downloaded it with.
Return to the Download preferences: if the speed you saw was near your max download bandwidth then click Apply and be happy, 'cause you're done here. If on the other hand it isn't, increase the number again by 1 or 2 and click Apply. Delete the download the re-download it.
Lather, rinse, repeat as needed.

IMPORTANT:
-Don't think that setting upload speed too low or completely disabling uploading won't affect your speeds, 'cause it will.
-Remember to be patient with the last step as going too fast might result in setting the number too high, which would have the opposite effect.
-DON'T forget to click 'Apply': every time you change something and are pretty confident that what you did was right, then click Apply. Don't forget it.

As a side note, I'm proud to say that any of my friends' Limewire's (including mine, of course) I've configured this way are going very fast, as in "going at 'Top Speed'", so I think that these pointers are not crap.
To any of the veteran members and/or connaiseurs of Limewire: feel free to make feel like an idiot if you think that what I wrote here is bull.

EDIT: If all else fails, then it's time to consider the possibility that your ISP is among the really "brilliant" ones who had the equally "brilliant" idea to throttle P2P traffic.
This is a link that shows some ISPs known to have chosen this course of action. Go there and hope you don't find yours on the list.

Also, here's a link to many helpful links (provided by Gnutellaforums' own Cleaning Lady ). Among them you can find a "speed test" page. Just remember to run the test many times at different times of the day.
I hope this helps at least someone...

__________________
iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

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