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I am using Lenovo computer having the following configuration: 516 MB RAM and 3.06 GHz CPU

When I installed 11.04, the system was getting very slow. From the Internet, I read an article that Lubuntu desktop are very light-weight desktop, so I installed it in Ubuntu. When I switched to Lubuntu desktop, the system got a little bit faster, but when I open YouTube site or some other video-streaming websites, the system gets slower.

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Adobe Flash Player (which plays Youtube videos) is a resource hog no matter what OS you use. You could try enrolling in Youtube's [HTML5 trial](, and your system might run a little faster--but streaming video on old hardware is going to be a touch slow no matter. – adempewolff Aug 23 '12 at 11:33
This site works better if you ask only one question per question. Please edit your question so that it only asks one thing and ask again the other. – Javier Rivera Aug 27 '12 at 12:17
Install the entire Lubuntu branch instead of the desktop alone. Plus a single cored 3.1 GHz with 516mb ram and trying to multitask? That is a no go – Dr_Bunsen Jul 21 '13 at 11:44
With that low amoount of RAM I would really consider if running more than one program at the time is really neccesary? What do you want the computer to do? You also talk about forcing a program to shut down, use xkill in a terminal and then click in a window that's hanged, problem solved. – Alvar Jul 21 '13 at 12:04

1. With the 516 MB RAM it would be very advisable to use LXDE/Lubuntu. I use it with 1GB RAM and the difference is huge compared to using Unity or KDE, and very significant compared to using Xfce/Xubuntu.

2.The way your computer lags in playing flash in Youtube is a different issue, as it is related not to your RAM or CPU, but to the graphic card (GPU). You have a powerful enough CPU but the Adobe Flash plugin has the odd quality of avoiding using CPU and putting all the load on your GPU. See this question and the answer there and the comment of izx:

Flash 11+ "attempts" (poorly, it looks like) to use the GPU (hardware) to "decode" the video instead of the CPU (software). Decoding is a fairly computationally intensive task, but most modern CPUs (except Atoms) will deal with 1080P HD without breaking a sweat. It appears that Flash doesn't seem to obey that checkbox and still tries to use the GPU.

(meaning the checkbox in Adobe Flash Player Settings telling it not to use hardware acceleration)

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Odd enough, using the HTML5 version of Youtube (which some recommend as a solution in this case) still brings my GPU to 100 degrees Celsius.

It seems that there are ways to put your CPU (more powerful) to work, and not your GPU (which is less powerful). My favorite solution to this is opening youtube in external player.

Lately I could not use the OpenWith Firefox addon to open youtube videos in VLC, so I recommend especially the Firefox add-on Smplayer context menu or the Youtube player that comes with SMPlayer (smtube). Install in Terminal (instead of Synaptic, which seems to give a version of SMPlayer that does not allow editing its Toolbar)

sudo add-apt-repository ppa:rvm/smplayer
sudo apt-get update
sudo apt-get install smplayer smtube

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or just Alt-F2

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To create a desktop icon the Lubuntu way:

enter image description here

3.To kill processes like you do in Windows, you need to start a Task Manager.

enter image description here There a different of this kind (gnome-system-monitor, lxtask, xfce4-taskmanager) and according to the desktop environment there are different ways of setting keyboard shortcuts for applications. But that would mean creating a new question (you already put two of them here!)

To kill now active window:Alt-F4.

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Hey, which theam you are looks good, could please share how to install above theam – Vijay Nalawade Sep 3 '12 at 11:35
i am in lubuntu and am therefore limited to gtk2 themes. if you like the original orange of the elegant brit theme: icons are malys-uniblue (…). window border is "turquoise night ob" – cipricus Sep 3 '12 at 11:41
GPU is not short for graphic card! it's short for Graphic processing unit (like CPU) it's just one part of the graphic card and not the entire card. It's like calling the whole computer CPU. – Alvar Jul 21 '13 at 12:06

Killing a process is easy once you know how. Assuming it's a GUI program (a program with a visible window), you can kill it this way:

  1. Press Ctrl+Alt+T to bring up a terminal window.
  2. In this terminal window, type xkill and press Enter.
  3. You cursor should turn into a cross.
  4. Click the window that you want to kill.

If this doesn't work for some reason, instead of xkill type ps -A (capital A is important). This will bring up a list of running processes, with process IDs at the left. To kill a process, simply type kill [ID]. For example, if the entry for Firefox looks like this:

15686 ?        00:24:23 firefox

you will have to type kill 15686 to kill Firefox.

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You can also use kill `pidof [executable]` as a quick command. – hexafraction Aug 27 '12 at 11:41

In addition to Kalle Elmér answer:

pidof firefox | xargs kill

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If there is another answer that is incomplete you should edit it. In its own right, your response does not resolve the original question, therefore cannot be accepted or voted upon. You have also an option to edit your answer with the FULL solution. – stephenmyall Sep 1 '12 at 18:05

Install the software called MiniTube. It is free for Linux and will greatly help your play YouTube videos, since it doesn't use Flash. Additionally, it allows you to skip all of the advertisements.

Lubuntu is great and not as bloated as Ubuntu or even Linux Mint.

Good Luck!

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