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Showing posts with label computer. Show all posts
Showing posts with label computer. Show all posts

Thursday, 1 March 2012

Raspberry PI : World cheapest computer is here : USD 35

Raspberry PI

This computer was created so that every student in the world can own a computer, here is the picture :


Here is the hardware spec :
ARM V6 700 MHz CPU
256 MB RAM
Micro SD Card slot
HDMI and TV out port
2 USB and 1 LAN

The processor is one that has power up many android smartphone. It has built in H264 HD video decoding capability.
This computer was meant to be connected to an ordinary TV or HDMI TV.
It has no hard disk but using micro SD card. Actually I am typing this blog using a system on thumb drive also.
It was powered by a micro USB input like most android phone in the market.
You may said the RAM is too small but I have been using Linux with 256 MB RAM before and it run a lot faster then Windows XP on 512 MB RAM and windows vista on 1 GB RAM !
The operating system will be GNU Linux

Wednesday, 12 October 2011

What is 64 bit Operating System ??

There are 64 bit Windows 7 flying around in the market. Actually new computers nowadays are preloaded with the 64 bit version..

The Limitation of 32 Bit Operating System
The old 32 bit version of Windows can only support up to 4 GB of RAM. And one thread (aka one program) can only access up to 2 GB. Doesn't matter how many RAM you put in.... Only 2 GB

History
Somewhere in the year 2000, Intel release this 64 bit CPU called Itanium. But it was too expensive and incompatible with existing 32 bit program.

After that, AMD release AMD 64 CPU. It is not a new design but just a minor extension of the Intel 386 instruction. Because it is cheap it came to wide acceptance.

Itanium are obsolete now. All 64 Bit Operating System and program are designed to run on AMD 64 nowadays.

Is it better ?
64 bit OS and program used twice the RAM comparing with 32 bit. But it run 50 % faster then 32 bit.

64 Bit driver are incompatible with 32 Bit driver. All 64 Bit driver must be signed by Microsoft if you want to install it. No such restriction on Linux.

32 Bit program will run on 64 bit Operating System with 50 % performance decrease. 64 Bit program cannot run on 32 bit Operating System.

Conclusion
If you are a video editor or a serious gamer or a database manager, you will see a big increase in performance of your PC if you upgrade it to 64 Bit. For ordinary users, there is no difference.

Tuesday, 13 September 2011

enbedded device taking over desktop and laptop ?

There has been many reports saying that embedded device (smartphone, tablet pc) will replace desktop and laptop pc soon. Is this true ? Is it good or bad?

Well, it is true that there are more 'embedded device' running then real pc. Depending how you define an 'embedded device' is. Linux is running on many router, modem, mobile phone, microwave oven, refrigerator, car entertainment system, car parking meter, dvd player and many thing. You have been a big user of embedded device or Linux without knowing you are one.

Lately the technology movement in smartphone is really amazing. Nowadays you can get a powerful processor and a real operating system on a cheap smartphone. You can run tweeter, facebook, bittorrent, checking email and typing letter on it.

All this happened because all this devices doesn't depend on Microsoft and Intel. So anybody can make a cheap thing out of it.

Desktop and laptop sales is going down because of these device. But they will survive because you need them to do more complicated thing like CAD, graphic editing and 3D games.

Tuesday, 6 September 2011

Why we should not buy iphone or ipad

I was sad because some of my friends spent their hard earn cash buying iphone and ipad. But form the technology point of view, they are low spec staff which cost 400% more than their reasonable price.

But the most important reason is because the software model the Apple is using. You can't just write a software and expect it to run on the 2 rubbish products. You have to submit to Apple and pay them money.

Even the super cheap smartphone has higher spec then these ipad and iphone. So save your money and buy a smartphone or netbook.

Thursday, 25 August 2011

Difference between 3 programming language : C++, Java & python

For persons who wants to write program for computer, here are some 
programming language they can choose from :
 
C++ :
C++ is a superset of C. Meaning that C++ is C with more features. 
Kernel of Windows 7 was written in C. Linux kernel was written in C.
Here is a simple C++ program :
  
#include <stdio.h>
  
int main (void)
{
    printf("Hello World !\n");
    return 0;
}
  
C++ are very complicated.It needs to be compile 
into machine native code to be able to run. But it 
runs very fast and used very little memory. 
A C++ program in Windows will not be able to run on Linux and vice vesa. 
A program for AMD 64 cannot be run on Intel32 machine.
C++ program can deal directly with your hardware and the programmer
must manage the memory of the program properly.
Java:
Java is a great programming language by Sun (now belong to Oracle).
The syntax looks like C and it has automatic memory management. But 
C++ program runs 10 to 100 times faster then java. Here is
a sample Java program code :  
 
package helloworldapp;

public class HelloWorldApp {

    public HelloWorldApp() {
    }

    public static void main(String[] args) {
        System.out.println("Hello World!");
    }

}
 
The  code must be compile to bytecode and load into 
your Java interpreter program to be able to run. But
the bytecode are portable across different OS and machine.
Java is simple but take a lot of writing to do simple thing and it 
is slow and take o lot of your computer memory.
 
Python :
Python is a cool programming language. It is very simple
and programmer can write a program in the shortest of time.
Here is a simple code program:
 
print " hello world !" 
 
 
Simple right ? Python code are no need to compile into anything.
You just run the text file with python interpreter program. Python
are slower then Java. But NASA and Wall street use it for their mission
critical application. 

Tuesday, 23 August 2011

difference between Intel Pentium G620 I3, i5 and i7

Many people asking me this question so I have better make clear explaination here.

First of all, from the technology point of view, the 4 thing is about the same. But Intel make different name for them for marketing and different range of pricing.

Here are some of the features of these LGA 1155 processors :


2 core and 4 core : i7 normally has 4 cores but the others has 2 cores except some expensive i5.

Hyper Threading : Useless technology by Intel. Only the Pentium G620 doesn't has it. You will see 4 cores on your OS but actually there are only 2. Another 2 are virtual core. The virtual core was generated using extra cycle from your CPU. The truth is if you have extra CPU cycle, you don't need hyper threading. The shit just confuse your operating system.

Turbo Boost : Only i5 and i7 has this thing. The CPU can increase speed by 30 % for a few seconds.  But this is just for temporary only. I don't see any benefit of this thing.

Clear Video : Only on i5 and i7. This thing can directly decode your H264 and mpeg 4 movie within your CPU (aka H264 hardware decoding) . But CPU nowadays are powerful enough to decode all these movies using software. Unless you want to watch Super High Resolution Full HD video (where to get this kind of video ?), you really don't need this shit. Do you know that computers nowadays can directly decode mpeg2 (aka DVD). But nobody use this features anyway because the software is good enough already. Software can be upgraded but hardware can't.

True 3D technology : This one on i5 and i7 only. can render 3D thing in the CPU. Useless unless you play racing game and 3D shooting game. And if you really serious into gaming, buy AMD.

Conclussion : It is all the 'price' thing. Buy i7 and i5 if you wanna show off you are rich. Buy G620 if you want to do serious work and wanna save $

Thursday, 18 August 2011

how to bypass government DNS blocking of certain web site

Last month, Malaysia has instructed all the ISP to block some file sharing website. Some of the sites are : www.thepiratebay.org filestube.com duckload.com megaupload.com and many others. Most ISP block it inside their DNS server. Users just change to a new DNS server and will be able to access all those sites.

What is DNS Server? DNS is Domain Name Server. Devices connect to each other using IPV4 address on the internet. Like : 206.678.1.5 or 235.456.23.5

when you key in an address on your browser like www.yahoo.com, the computer will ask the DNS server for the IPV4 address of www.yahoo.com. And the DNS server will reply something like 243.326.345.6

Just change the DNS Server to google DNS server and you can bypass all your ISP blocking.

In Windows XP:
Control Panel  -> Network Connection -> Local Area Network (Or Wireless Network) -> click on TCP / IP -> Properties

change your DNS server to 8.8.8.8 and secondary 8.8.4.4

In Windows 7 :
Control Panel -> Network And Internet -> Network And Sharing Center ->Manage Network Connection
Right click on your connection and select Properties. Click On TCP/IPV4 and select Properties

change your DNS server to 8.8.8.8 and secondary 8.8.4.4

In Linux :

edit the file /etc/resolv.conf


Wednesday, 17 August 2011

Making computer (even) faster

Many people have a very high end computers but it is as slow as a 486..... Some takes 5 minutes to boot up....some takes 30 seconds to open their Microsoft Word ( Most computer dummies use Microsoft Word). So what is the problem ? Any solution ?

Well, most people using 95 % of their CPU power to do non productivity job. Another word : rubbish. Like : Graphic enhancement for their desktop, scan virus and many thing that doesn't make any sense.

So first : Disable Graphic Enhancement : Go to control panel -> System -> Performance -> Setting and select 'adjust computer for best performance'

Second thing : Add exception of 'explorer.exe' to your anti virus program. Even better just get rid of the anti virus program. Switch to Linux and you don't have to worry about virus anymore.

Run 'services.msc' and disable some of the rubbish services. Like 'System Restore', Remote registry, secondary Logon, distributed link transaction, BITS, Fast User Switching.

Run this 3 commands:

fsutil behavior set disablelastaccess 1
fsutil behavior set disable8dot3 1
fsutil dirty set c: (if c is your system drive)

reboot.

get rid of all your temporary files and temporary internet files using disc cleanup

After that, run this :
defrag c: (if C is your system drive)