Do I need to erase my hardrive?

Hi!
I tried the Malware Forum first - did what they suggested, ran all the scans and my logs were clean. They said my issues were not Malware related so I should try the Software or Networking forums.
I hope you can help me with this problem.
I've been having some trouble with internet speeds. The computer itself is working fine and fast but the internet starting acting up a few weeks ago - became very slow - some pages would not open and it had trouble connecting with servers...
I use Optimum and I called to report the problem to them. At first they said that they noticed the speeds were off and told me to pick up a new modem at their center. So I hooked up the new modem, still had problems. They sent a few guys out - they replaced the modem once again - different brand - and the internet was still slow. They told me I must have a virus.
I came to your site - went through your 'Read me firsts' and I tried going through the steps of 'understanding, cleaning and preventing spyware' and also 'malware removal, cleaning procedure'. There were a few trojans found and I removed them. Later rescanned and everything came back clean... Computer was running ok for a few days - then I was online and avast found a virus that kept repeating itself faster than I could close the box - sort of froze up - so I went into safe mode tried another series of tests (panda virus pro, pocket killbox, super anti-spyware, malwarebytes, cccleaner) and the tests came back clean - no virus or threats found - internet was ok for a day then slowed down again.
I called Dell and after 3 hours on the phone (with someone I could barely understand) they had me remove all the tests I had just used, had me run ginfix.exe and a bunch of other tests. They were coming back clean... the last thing he suggested was that I have them wipe my hardrive completely and start over and said they would send me an external hard drive for $79 so I could move everything off my computer (pictures, ect) and that I should get rid of Avast and purchase Norton 360 Premium version.... I will do what I have to to fix the problem I just want to be sure it's really necessary and its not the cable company. Any help or advice would be greatly appreciated. The last thing I did was contact your Malware forums and as I said the logs were clean. Do you have any other suggestions for me? Thanks!

 

Do a speedtest.net to test your connection in safe mode for some ammo. I agree with plodr, it also took some 4 visits before they got it right. They have to measure the signal strength, that's paramount and changing out my lines finally did the trick.

 

You might also consider downloading a Live Linux ISO which you would write to empty CD or USB flash drive. Puppy Linux is only about 160mb. Then boot from the CD/USB and run a second speedtest.net and compare to the one under Windows. If both are bad it would seem to rule out your current Windows installation as the culprit.

 

http://www.wugnet.com/myspeed/speedtest.asp

Would this help?

 

http://www.wugnet.com/myspeed/speedtest.asp

Gives me a VERY different result (for me) from the old standard www.http://speedtest.net/

 

Thank you all for responding!
As for Optimum Online - I have TV, internet and phone through them. I do notice with the upstairs TV it takes several seconds longer to switch between channels and the going through the guide is pretty slow too. When the two cable guys were here testing and hooking up the new modem they were only hovering around the computer/modem/phone area (the phone is right next to the computer since it's hooked into the modem) They didn't walk around inside the house at all. I'm not sure if they'd need to. I will bring that up the next time I talk with them.
I went to speedtest.net. I tried it a few times over an hour. Results were:
Test #1
ping 11 ms
download 1.24 Mbps
upload 4.80 Mbps

Test #2
ping 11 ms
download 5.44 Mbps
upload 4.55 Mbps

Test #3
ping 11ms
download 35.54 Mbps
upload 5.18 Mbps

So they changed alot - the last test took alot longer than the first two to finish - the upload almost stopped around 29 Mbps then shot down to around 5 Mbps. But that's how the service has been - Sometimes a page will open on the first try then the next will take two or three tries....

I also went to the Wugnet site. I tested there yesterday and got:
download 1.24 Mbps
upload 4.80 Mbps
Then tested again this morning before coming here. It said:
download 4.85 Mbps
upload 126 Kbps

I want to try Live Linux ISO but I'm really confused about how to download and use it. I have never booted from a USB drive before.

 

To install your Linux - download it as you would download anything else, then burn it to CD, or put it on USB, then, while booting up press F8 repeatedly until you get your BIOS menu. Change your boot menu within BIOS to boot from CD or USB, not all BIOS menus will allow you to boot from USB, but it SHOULD allow you to boot from your optical drive (cd/dvd) .
If you have problems doing that post back here with your BIOS version and somebody will help you .
If you need more help, be sure to include you computer model and OS version .

 

I downloaded Knoppix and booted from a USB. It was having trouble working on the sites I had used before so I did a speed test at testmyspeed.com.

The results were:
test #1
download 18478 kbps
upload 844 kbps

test #2
download 13369 kbps
upload 1247 kbps

Then I rebooted under normal Windows Vista and went to the same site.
Results:
Test #1
download 10040 kbps
upload 2067 kbps

Test #2
download 21944 kbps
upload 806 kbps

The results seem kind of similar... would that mean Windows isn't the problem?

 

Strangest thing happened - last night out of nowhere my internet started working again. The speeds are back to normal. I hadn't changed anything since the last time I checked (that afternoon) or tried anything new. But I did notice a few Optimum vans driving around my area today... maybe that had something to do with it. I just hope it stays this way!
Thanks you all for your help - I really appreciate it!