Wi-Fi limiting speed?

[#1]

Having just upgraded to fibre I've been very pleased with the speed I'm getting, substantially better than the guaranteed minimum. However I was initially disappointed to find it was less than the guaranteed minimum until I discovered that this was only on the wi-fi connected PCs. The single PC that is wired to the hub gives a speed test reading of around 75Mbps/18Mbps but a similar machine running the same version of Windows but connected via an Edimax EW-7711In wi-fi adapter only gives around 55Mbps/18Mbps and an old laptop running Vista is worse than that.

The Edimax card claims to be good for 150Mbps so I'm wondering where the bottleneck is occurring. Most of the time the only devices connected via wi-fi are the pc and a couple of phones and I can't see the phones hogging the bandwidth.

55Mbps is perfectly adequate, I'm just curious why the wi-fi is so much worse than wired.

[#2]

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@Buggwrit wrote:

The Edimax card claims to be good for 150Mbps

It actually claims to be good for "up to" 150Mbps. So in ideal conditions, next to the router, with no interference & no overheads. In other words unachievable in the real world. You could try swapping WiFi channels on the router to each of the primary channels 1, 6 & 11 & see if that helps. But if you need faster you'll probably need to change the card to one with higher specs (assuming your router supports it).

You say the laptop is old. Depending on how old the card in that may only be "up to" 54Mbps.

[#3]

Hi Dabbler, thanks for your reply.

The distance from hub to Edimax antenna is 6.8 Metres (22' 4") and it's in line of sight (the hub's in the cloak cupboard and the PC is at the top of the stairs). The only structure in between is the door which is wood/fibreboard so I'd be surprised if that reduced the maximum claimed bitrate by half. The signal status always shows at or near maximum.

As I said, I don't need faster I was just puzzled by the discrepancy. I wasn't surprised the old Vista laptop was bad as I expected it would have an inferior wi-fi system.

When I get back from hols I might try your suggestion of changing channels if I'm at a loose end.

[#4]

As I said, the stated speeds are theoretical maximums. The first thing to consider is that WiFi is half-duplex, meaning that only one device can talk at a time. Even with only two devices talking to each other (your PC & the router), the 150Mbps is shared. So pretty much instantly halved before you even start to consider other factors.

All in all, 55mbps from a 150mbps device is actually pretty good. Probably due to the factors you mention.

If you Google "real world wifi speed" you'll probably find better explanations than my ramblings.