Download Speed on Windows Vista Has Dropped Dramatically

The Problem

The download speed on my Windows Vista have dropped from 300kb/s to around 20kb/s. It took me several attempts to find out what the problem was.

It first seemed to me that my ISP was in a technical difficulty state. I am on a dual-boot system with both XP and Vista. In order to verify that Vista was not the cause of the problem, I booted into Xp and did some speed throughput test. Surprisingly my download speed in XP was normal (300kb/s). Clearly the cause for my slow download in Vista was the Vista itself.

Now it comes the tough part: Which part of the Vista caused the problem? I've tried to uninstall/reinstall programs in my computer and used msconfig to disable startup programs. Zone Alarm was kind of suspicious since it was beta version (stable version was not available for Vista at that time), so I ran the uninstaller. That didn't help either. I have even tried to boot to the safe mode. None of which did any good.

The Solution

After exhaustive diagnoses, and without getting the problem fixed, I decided to uninstalled my NIC (Network Interface Card) driver, which was an onboard Realtek Ethernet card. So I removed it from the Device Manager. A popup prompted me whether to delete the driver software for this device, I chose Yes. After uninstalling, I issued an "Scan for hardware changes" command to the Device Manager, it reinstalled my NIC. As soon as my NIC is installed, I tested my internet connection speed. It mysteriously went back to the normal (300kb/s).

Uninstalling NIC:
Remove NIC

Make sure Delete driver software is checked:
Remove NIC Confirm


I have no idea what has happened, I guess it was a problem with the NIC driver. The important thing is the problem now is resolved. If you have similar problem and run out of solutions, it worth to give it a try.

24 Comments Download Speed on Windows Vista Has Dropped Dramatically

  1. Jerome Samuelson

    I had Vista download problems with any file that had or music. 25-30 Kb/sec on wireless. Hard cable connection was much better. Speeds varied slightly with the local router (I toured coffee houses to try to define wireless problem). Other stuff seemed OK, software etc. General Internet navigation was OK.
    Local Geek squad was baffled. I returned the computer and am having my ancient Toshiba machine repaired. It has XP, an OS with which I've had no problems. I may order a new PC with XP rather than Vista, or go Mac (except its business and financial software is not too welcoming to my Windows Quicken files).
    Any thoughts would be welcome. Thanks

  2. nick

    hey thanks, this really did work for me. i have 5Mb/s internet yet my network is really old so i usually get around 300kb/s on my XP. i just got a vista laptop and the loading speeds were fine but the download speed was 25-45 kb/s.
    this worked, now i can finally stream videos again.

  3. J.P. Morgan

    This worked on a USB wireless card that was preforming poorly. My download speed jumped from 130Kb/s to 360Kb/s. Thank you!

  4. Sven

    Dude your my Hero. i tried everything to get my net speed back to normal after intalling vista ultimate, was about to give up when i came across your thread. Thanks a lot, you saved my computer from the trashcan :D!

  5. Johnny


  6. kevin

    I did what you said and after reinstalled my NIC device it said the divice was not successfully installed . Can you give me a solution to this plz .

  7. Scott

    Stupid Vista! Thanks for the tip, I've run into this issue on 2 separate computers and this appears to fix the problem. I've got a Broadcom 802.11g network adapter.

  8. Dataneto

    Just great. It also works with Vista in Hebrew. Went back to 700 kb dowload.

    Thank you.

  9. Christy

    nope didnt work(btw i just updated driver software) i still have the same! jeez this sucks

  10. Chris

    I have a Dell XPS420 Vista SP2 connected to Fios with and ethernet connection directly to my Actiontec Router. My average speed tests are 6mbps to 10mpbs. I ran the test and my lowest speed was 2mbps this evening. I restarted my system and had a 8mbps speed test result. I am paying for the 15MB Down and 2 MB up. With my laptop, connect through wifi, I am getting my full 15.3 MBps running the exact same OS. This issue is fairly recent with my Dell.

    Un-installed the driver as stated above. Issues solved. Thanks

  11. sean

    Hey, thanks man, I have been arguing with my ISP for like 6 months now, and it was all my PC the whole time. I did step by step what you did, and now i get 20mgbt DL, thats WAY better than .2mgbt DL.
    Thanks alot:)

  12. Hosting Reviews

    Where were you with this post about a month ago when I had the problems you listed with speeds in Vista?

    I managed to do this same procedure on a whim and it also fixed my speed issues.

  13. Jure

    Didn't work... Unfortunately. I'm still at 6 Mbit per second download speed as opposed to 20 Mbit. I know, it's fast, but should be much faster. HP tech support had me do all these crazy things on my computer to try to help but nothing changed. I tried this, no change. Makes me think my ISP really did lower the download speed (I live in South Korea, so calling the ISP isn't that easy because of languagee issues ;)

  14. Jeff Honeyager

    I have wireless and ethernet - first tried the wireless - no luck and now I can't connect via wireless after deleting the driver and reinstalling it.

    Tried the ethernet - hard wired - now it gets 90Kbs (I'm paying for 10Mbs) - and now my vonage modem is not working.

    Vista stinks.

    I don't want to get Windows 7 - I may have to...

Comments are closed.