My laptop is a Toshiba A300 system. My problem is if the power supply is connected the unit just keep on re-starting but if the unit is unplugged I can use it till the battery is discharged which is about two hours only. Then I will have to recharged again.

Can you get to safe mode? Remove ALL Media, DVD, CD, USB, unplug, remove battery, plug in, reboot.

The power adapter needs to be checked or better still sub out with a second power supply.

Hello,
When you will increase the ram your laptop will be fast soon.
You can increase 4 GB maximum.
For dissemble follow bellow the link
http://www.irisvista.com/tech/laptops/Toshiba-Satellite-A355-A355D/laptop-disassembly-1.htm

Maximize your Toshiba Satellite A300-ST6511 mobile computing power and add more memory. Trust PRO Memory Upgrade to provide dependable expansion options for your laptop or notebook with a Toshiba Satellite Small Outline DIMM RAM upgrade.

• Your Toshiba Satellite maximum RAM capacity: 4GB
• The Satellite A300-ST6511 has 2 memory slots or sockets
• This Satellite module upgrade PIN count is: 200-PIN
• The memory speed is: DDR2 800MHz, PC2-6400
• The DIMM type for your Satellite A300-ST6511 is: SODIMM, SO-DIMM, Small Outline DIMM
• For4 diassamble the
  

Hope it help you.

hi dis is ravikanth when ill charging my laptop toshiba A300 its automitically restarting what is the problem plz tell me

Replacing the DC Power Jack on this model of Toshiba Satellite A300 series, is SWEET!

{The Toshiba Satellite A305-S6857 Notebook PC, is part of the Toshiba Satellite A300 series of Notebook PC's}

No de-soldering, or soldering is needed.
The DC Power Jack is a DC Power Jack Harness.

The DC Power Jack is connected to a cable (Wires) that end in a connector, and the connector plugs into the motherboard.

To repair the problem you just replace the power jack harness.

A) Guidance given with instructions, and a pictorial guide, (Click on each photo to enlarge),

http://www.irisvista.com/tech/laptops/Toshiba-Satellite-A305/laptop-disassembly-process-1.htm

The above is Page 1.
To go to Page 2, and Page 3 ,click on the white page number at the top, or bottom of the page.
{Page 1::Page2::Page 3::Find another model }

Page 2, Step 17 shows you the DC Power Jack Harness, and where it connects on the motherboard. (Small white rectangular connector)


B) This is a link to a free Service Manual for the Toshiba Satellite A300 series of Notebook PC's,

http://www.tim.id.au/blog/tims-laptop-service-manuals/#toc-toshiba

Go down to the 11th line. The one that starts with Satellite A10.
Scroll across, and click on > A300

This is a PDF file.
Allow up to 30 seconds after you click on the file name A300, for the first page to come up.
It may also take additional time for the file to fully download.


C) Remove ALL power to the laptop before you begin.
Remove the AC adapter (Charger) and Battery

D) Observe Anti-Static Precautions

It is Advised to buy and wear an ESD wrist strap, and connect the alligator clip to a good ground source.

{For one example I connect the alligator clip to the metal frame of an empty desktop computer case}

Your body carries Static electricity.
Static WILL fry out (Short Circuit) the hardware components inside a computer.

Using an ESD wrist strap, and connecting to a good ground source, will relieve your body of Static, and help to ensure your laptop is safe from Static shock.


E) Use a multi-compartment container for the various screws you will remove.
Mark each compartment for the area the screw/s come out of.

There may be as many as 60 screws, and 12 different types.
Do NOT mix them up!

If no multi-compartment container is available, you can substitute with a clean egg carton.
Mark each egg holder.


F) Make a record as you disassemble. It's nice to have a record you can go back to in case you are interrupted, and to have a record that YOU understand.

Make notes and drawings, use a camera, or video cam if available.
{Use Good lighting}

From a quick search,

1) http://compare.ebay.com/like/170510661911?var=lv&ltyp=AllFixedPriceItemTypes&var=sbar&rvr_id=184497530091&crlp=1_263602_309572&UA=WXF%3F&GUID=e35d70b712c0a0aa14823c52ff69e46d&itemid=170510661911&ff4=263602_309572

Another one,

2) http://www.notebooksolutions.ca/zc/index.php?main_page=product_info&products_id=3231&zenid=90f1860bdc1b624a9122b76394734645

Regards,
joecoolvette

Follow the link below to download the drivers. Just select your Operating System.
By the way i found the drivers for the following system: TOSHIBA SATELLITE A300

Click here to follow the link.
Hope this helps,
Please feel free to ask me any further.

Power supply cord is faulty. You can get another from newegg.com or amazon.com or ebay.

The lights can be turned on and off thru the bios and thru hw setup program on the pc

take out the battery and put it back in and the manually turn on your pc

if you say that either the battery nor the adapter was tested and seemed working fine but not actually giving power to the laptop itself then the problem is the motherboard from your laptop i m afraid
sorry i have no idea about the service center in tamilnadu