Reason why internet connection work very slow

There are several things to consider.

1. You are at, or beyond, the distance limits of your router (wiresless transmitter). Move closer to see if the problem is resolved.

2. There is interference between your PC and the wireless router, such as a 2.4GHz cordless phone, microwave oven, flourescent lights, etc. Temporarily disable the devices, one by one, until you determine the problem.

3. The antenae on either your router or PC is loose. Tighten each.

4. Your PC may be infected with a virus, trojan, or spyware that is eating up your bandwith, and causing packet loss.
Download the programs linked below. Install them. Update them. Scan your pc with them, and do so weekly.

If you have System Restore turned on, the Restore files may be infected, and trying to reinfect your pc. I turn off that feature, reboot to delete the files, then turn it on after a full system scan with AVG.
Turning off System Restore.
(right-click My Computer, Properties, System Restore tab, check the box to turn off System Restore on all drives.)

Restart your PC, and hold down the F8 key.
When you see the Boot Menu appear (black screen white letters), choose SAFE MODE.

Run a FULL SYSTEM SCAN with AVG.
You may heal or quarentine anything found.

You can also run Spybot and AdAware while in Safe Mode. I suggest you do a full system scan. Get rid of anything they find.

To exit Safe Mode, just restart your PC normally.

AVG Antivirus - Free Antivirus Software
Ad-Aware - Free Antispyware Software
Spybot Search&Destroy - Free Antispyware/Antitrojan Software
Trend Micro HijackThis - Free program to turn off Browser Hijackers
CW Shredder - Free program to remove the ability of malware to point your browser ot CoolWebSearch and its affiliates

One REALLY great feature of Spybot Search&Destroy, is its ability to help your PC block known spyware/hijacker sites. Just use the Immunize feature.

Hope this helps.