Slow network transfers between XP machines.

[TheNuker]

I'm having a strange issue for a long time that I've never been able to fix.

I've a desktop, wired to a d-link 524 router (54mbps), and a laptop connected wirelessly to it. Both machines are running fully updated XP SP3, clean install, no AV/Firewalls in between. File transfers between both computers never go above 2MBps, unless I connect the laptop to the router by a lan cable. That way, I can get up to 6~7MBps transfer speeds, which are reasonable to my router speed.

HOWEVER,

When both machines are running Vista, this problem doesn't happen. Transfer speeds between machines (desktop wired, laptop wireless) always go at full speed (nearly maxing out the router's 54mbps limit). This doesn't apply when one computer is running Vista while the other XP. So, only Vista-Vista setup works properly.

I've tried different drivers for the laptop's wireless nic, and also tried different nics at desktop, and none helped. I believe this is some kind of configuration at windows XP, but I've searched quite a lot and so far to no avail. Can anyone shed some light on this?

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tl:dr version:

Wired Desktop XP --- Wireless Laptop XP = 2MBps tops;
Wired Desktop XP --- Wired Laptop XP = 6~7MBps (which is good considering it's a 54mbps router);
Wired Desktop Vista/XP --- Wireless Laptop Vista/XP = 2MBps tops;
Wired Desktop Vista --- Wireless/Wired Laptop Vista = Almost constant 8MBps (nearly maxing out the router capacity);

HALP!

 

[Madwand]

Wired Desktop XP --- Wireless Laptop XP = 2MBps tops;
Wired Desktop XP --- Wired Laptop XP = 6~7MBps (which is good considering it's a 54mbps router);
Wired Desktop Vista/XP --- Wireless Laptop Vista/XP = 2MBps tops;
Wired Desktop Vista --- Wireless/Wired Laptop Vista = Almost constant 8MBps (nearly maxing out the router capacity);

Standard-g ("54 Mb/s") doesn't actually give you 54 Mb/s throughput. Under ideal conditions, it gives at best around 22 Mb/s actual throughput. As 2 MB/s = 16 Mb/s, your wireless transfer is right in the normal range for standard-g.

What's strange is your report that Vista wireless transfers are hitting 8 MB/s = 64 Mb/s -- this is actually impossible any way you look at it -- much higher than the expected actual ~22 Mb/s wireless throughput, and even greater than the marketed maximum underlying data rate of 54 Mb/s.

I guess that your file sizes may be too small to give accurate results, or that something else is happening. Some Vista configurations also have a bug in the Task Manager / Networking which display twice the actual transfer rate (but even this bug wouldn't be enough to account for all your discrepancy). The file transfer dialog is accurate for large files in my experience, as is (large) file size / actual transfer time. Perhaps you were actually wired when you thought you were wireless? BTW, the wired ports on a standard-g "54 Mb/s" router should be 100 Mb/s, and unlike wireless, it's possible to come close to this speed for actual throughput.