Internet speed dropping badly

Hi.

My internet speed has dropped badly and I am not sure what's the reason. I'll try to figure it out, and if it stays like, this, I'll obviously try calling the ISP.

I'm using a Scientific Atlanta router. I wonder, how would I know, if someone's stealing my wireless? It has a password and I was told it's safe against neighbours. Well, that's what the tech guy said when he set it up.

Any ideas on what could be slowing the internet speed dramatically?

2nd question:
I've been using 2 different computers on the same internet connection, and HP dv600 Windows Vista laptop is way slower compared to another PC with Windows XP, which has similar hardware specs. There is an extreme difference when browsing internet. The response time difference is huge even on very light websites.

I did not find anything that could help me on google.

Thanks in advance.

One way of checking is to look if there's an unknown computer in the active sessions list in the router. You can also connect a HUB between your router WAN port and the ADSL and connect a packet sniffer to check the IP activity.

Speed drops can be caused by many things. ISP has problems, your ADSL modem/router is on the way of breaking down/is overheated, you have gotten some malware, you have just installed a bad driver and so on...

Rather than basing speed off of how long a website takes...why don't you start by using www.speedtest.net. That will give you raw current bandwidth by both computers. If there's a difference between those two computers, then your problem is within the slow computer itself.

I tried using speedtest.net actually. I had used it before, but it did not work yesterday. It didn't start checking my download/upload speed and got stuck right when I chose the server on the map. Actually, quite many websites did not load at all or loaded very slowly.

I got the impression that there was some sort of a bottleneck.

Anyway, upload/download speeds are as good as usually today, and I can only wonder what was going on yesterday. Running network diagnostics on Vista did not find anything wrong. Resetting the router and PC did not do anything as well.

I had also used speedtest.net before to compare both computers and there was almost no difference.

If you want to try a off continent server you can try www.bredbandskollen.se. Press the 'Starta mätning' button and your net will be checked (skicka = uplink, ta emot=downlink). In my case up 24 Mbit / down 47 Mbit :)

If your tech didn't TELL you the wireless password, he might have used the COMPANY SUGGESTED one, like pass@word. Anyone having the same thing would know this...