Router speed drop solved2006-01-22 (updated: 2014-08-17) by MrFlimpy
Tags: router, speed, WGR614, BEFCMU10, cable modem, electric noise, throughput
I've been lurking here for a while trying to solve my speed problem. Thanks to everyone for all the great tips, but I had to laugh when I finally figured this one out. Maybe someone else can use the tip:
I just got upgraded to Comcast 6Mbs, but was only getting throughputs in the 2-3Mbs range, with an occasional 4.5Mbs, and an occasional 1Mbs. Really frustrating. I tried all the tweaks here. TCPOptimizer is an awesome little program, and seemed to make some marginal, but inconsistent improvement. I got rid of ZoneAlarm since v5 seemed to cause a problem even though I had v6. No software firewall, and new software firewall: same problem. No antivirus software, and new AV software: same problem.
I have a Linksys BEFCMU10 (the original version) cable modem, and my main router is a Netgear WGR614 v1 wireless router. The wireless is turned on and used, but not for this connection. All the connections are wired Ethernet. Lot's of posters here have newer versions of those things, but my same problem. I considered buying new equipment, but it turns out that even this old stuff works perfectly, as you will see.
Going straight from the modem, I get full 6Mbs+. Through the router, it drops by half or more. During testing, I was cycling things on and off, switching the wiring when I finally stumbled on the problem. I was connected directly through the modem, but had the router turned on, and my speed dropped by half! I figured I had the wiring wrong or something, but nope, no part of my system was connect to the router. I have a homemade wood rack, and the router sits just above the modem. I could do a Speakeasy test wired through the modem getting 6Mbs, and watch the speed drop as I powered up the router.
So, the problem is: electrical noise! All the cables are shielded, and the power cords are segregated from the data cables, so the noise is coming directly from the devices. And low and behold, when I separated the router and modem by a few slots on my rack, I'm getting full speed minus about 10%, which is probably reasonable for router overhead and marginal residual noise. I imagine a lot of you out there have your router sitting on top of or below your modem. It's a stupidly simple solution (although it took me a week to stumble on it): if your having line speed problems, try separating your router and modem.
Hope this tip helps someone out there. And thanks for everyone else's help.