Massive Speed Gain Through Raising RWIN

I just wanted to share my experience with regards to the above. I found that my wireless download speeds almost doubled through increasing RWIN from the default, which was around 17000, to over 201280. I am really impressed by the effect that this has had. I hope others might benefit from this.

P.S I am using XP. I gather this tweak does not work on vista.

In reply to a post by has:

P.S I am using XP. I gather this tweak does not work on vista.

More accurately, the tweak shouldn't be needed on Vista because it works it out for itself.

I take your point about vista. Interesting how much of a difference it has made on my xp setup - the impact mainly being on my wireless connection (Seems less significant on ethernet - where speeds were high anyway)>

I noticed on windows 7 (I expect vista be the same) that autotuning doesnt increase rwin above 17k on my wireless.

If you have not tried TCP Optimizer yet I would suggest you do. I use both Dr TCP and TCP Optimizer and found the latter to be useful to tune wireless parameters like RWIN and MTU when I moved from 2 Mbps to 8Mbps to 20 Mbps packages with different ISP's. RWIN went up from around 20000 to ~ 500,000 at the higher speeds. TCP Optimizer is also able to determine the optimum MTU for your line using a quick iterative technique - which is quite laborious to do manually.