hi. i am on a 4Mbps DSL internet line. i have a strange situation which i hope somebody here would be able to figure out and tell me what's going on.
i have 3 PCs (all running XP SP3) connected to the internet through a router. i noticed that direct downloads (http/ftp) on the 2 PCs that are connected to the router wirelessly are capped at about 50-60kb/s per download. just to clarify, i can still achieve a full download speed of 400kb/s in total, but just that each download is capped at 50-60kbps. on the other hand, the PC that is connected directly to the router via ethernet cable is able to download at well over 200kb/s per download.
if i download 1 file, the transfer rate is capped at 50-60kb/s.
if i download 2 files, each file is capped at 50-60kb/s.
the total download speed is 100-120kb/s.
if i download 8 files, each file is capped at 50-60kb/s.
the total download speed is 400-480kb/s.
on the ethernet PC, there is no limit to the transfer rate for each download. eg. if i download 1 file it can reach over 200kb/s.
so far i've attempted the following:
- tried changing routers, no change.
- wireless signal strength on all wireless PCs are "very good" to "excellent" and speed test results are optimal at 4.3Mbps.
- tried connecting one of the wireless PCs to the router using an ethernet cable instead. download immediately increased to over 200kb/s.
- tried disabling QoS on the router and wireless adapters, no change.
- tried running Speedguide.net's TCP Optimizer on "Optimal" settings. downloads on ethernet PCs immediately increased from 200kb/s to over 400kb/s (great improvement!). wireless PCs also showed an increase from 50-60kb/s to about 120-150kb/s (also improved). there still seems to be a cap on the wireless PCs and if you look at it, despite the improvement the ratio of download speed between wireless and ethernet PC remains the same. so the problem is still there and doesn't seem to be related to RWIN or TCP Optimizer.
one last thing to note is that, although direct downloads are capped at 50-60kb/s the wireless PCs are able to stream/download videos from video streaming sites eg. youtube, vimeo at max speed of over 400kb/s. i can stream 1080p videos very smoothly on these sites. i also used the site keepvid.com to generate download links from youtube and vimeo and was able to download at over 400kb/s.
i hope somebody can help me. this problem has been plaguing my mind for a seriously long time.
my tweak test result: