DSL: Improve Your Speed, Part 3 - The Naked PC Newsletter (#3.08)

by Lee Hudspeth

Many thanks and a tip of the hat to TNPCer Jerry Newman for pointing me to the DSLReports Web site for optimizing a DSL connection.

If you have DSL you start wondering if you're getting the throughput you're paying for. I've scratched my head and puzzled, "Is the Internet just slow today or has my provider dropped the ball?" The good news is that you can test your connection's downstream and upstream speeds right from the DSLReports Web site. What's more you can study their plentiful, well-documented tips on how to optimize your system settings to get all the speed you can from your connection.

The speed test link is:

The tips link is:
When you get to this page select your operating system (Windows, Mac, UNIX, etc.) from the "Jump to" list box then click on the Show button.

After having performed the tests numerous times, and having read and applied the tweaks, I recommend you follow these steps.

1. Since this is a Registry hack, all the usual caveats about editing the Registry apply. Before doing anything else, you want to see if by some happenstance your system is already optimized using the Registry "DefaultRcvWindow" hack.

1.a. Click Start, choose Run, type "regedit" and press Enter.

1.b. Browse to the key:


1.c. Check to see if there's a value named DefaultRcvWindow.

1.d. If there is no DefaultRcvWindow value, then your system is not yet optimized; if there is, note its setting but leave it alone for now.

If there is a DefaultRcvWindow value your system may have been optimized already.

1.e. Close the Registry Editor.

2. Close all running applications.

3. Start your browser and clear its cache. For IE5, select Tools, Internet Options, click the Delete Files button then click OK. For Navigator, select Edit, Preferences, Advanced, and click on Clear Memory Cache and Clear Disk Cache.

4. Close your browser then re-open it to the speed test link.

5. Follow the DSLReports steps 1-4 (use the Verbose test mode), remember to select the nearest download speed (nearest to what you're paying for) from the speed drop-down control, click the Test button and wait for the test to finish. The test takes about 30 seconds on my 768/128 Kbps downstream/upstream DSL connection.

My first-time test results--not having applied the DSLReports performance tweak--were 391/121 down/up. That's 50% slower on the downstream side than what I'm paying for! Certainly a non- optimized situation. So I followed their suggestions regarding implementing the Registry DefaultRcvWindow hack. Here's what I did.

1. I downloaded one of the ready-to-go REG files that will add the correct registry settings for you automatically. (See the table in the middle of the Windows tweaks page.) I opted to use the "Medium (32KB)" REG file for Windows 98: Rwin98-m.reg.

2. Once I had downloaded the REG file, a quick double-click on it in Windows Explorer updated my Registry. It's appropriate to click Yes when prompted "Are you sure you want to add the information in <path>\<filename>.reg to the registry?"

3. Next, and this is critical, I restarted my PC. Before you retest the speed connection, if you really want to be meticulous, clear your browser's cache and restart it. (I did.) Now go to the speed test link and perform the test once more.

My second-time test results were 624/82 Kbps. On the downstream side that's a 1.6x improvement. I FEEL THE NEED, THE NEED FOR SPEED! For a week I continued to run these tests daily by removing the DefaultRcvWindow value, rebooting, re-testing, then applying the DefaultRcvWindow hack again, rebooting, re- testing... you get the picture.

My results are consistently averaging 680 Kbps downstream OPTIMIZED and around 390 Kbps UN-OPTIMIZED. I've also been cross-checking the DSLReports test results by downloading the same large file with an FTP client. T.J., upon following these steps, also got a nice kick: a 50% improvement in his downstream speed.

Folks, if you have DSL I STRONGLY recommend you run through this procedure. It's given me on average a 60% improvement in my download times.