Random MAC problem

[Pebofin]

I connect to the net via my university. I can only do this is XP64 since in XP, the university detects a changing MAC address. I have not always had this problem so I don't understand why I have it now. I've reformatted and reintalled XP many times trying to fix, but no luck. I've tried the drivers that came with the mobo and the latest ones available on the web.

System looks like this:

A8V-E Deluxe
AMD64 3000+
2x512 DDR400 Corsair VS RAM
cheap 20-pin 400W PSU.
160gig Maxtor HDD
1 DVD RW drive
Leadtek 6600GT
Leadtek 2000XP TV card.

The network adapter comes with the mobo and is a marvell yukon one.
Back in the days when it used to work in XP, it's possible I had just 1 512 RAM stick.

I want to blame the PSU, because I don't mind replacing that. Unfortunately I have no idea why I'm having this problem, so any help is appreciated.

Thanks.

 

[spidey07]

your mac shouldn't change unless some kind of software changes it. virus?

ps - I've never heard of a network card just up and changings its address. That is burned into the card unless you change it in the driver.

 

[Pebofin]

I've formatted the HDD completely many times trying to fix this. So presumably that would "kill" any virus. I can't find anything similar on the web, so I'm really stuck here. What really baffles me is that it worked before, and now after a fresh install it doesn't work.

 

[spidey07]

That definately is very, very weird. I guess you could have a flaky network card. They're cheap so try a new one?

 

[Pebofin]

If the hardware is at fault, then it's odd that it works in XP64. I'll try a new one on Monday if I don't solve my problem before then.

 

[spidey07]

you're right, it doesn't make any sense.

But sometimes hardware problems never make any sense.

 

[ScottMac]

Do you connect through a SOHO firewall?

Have you set a "Locally Administered Address in either XP or XP64?

You could try loading Ethereal (www.ethereal.com) and see what the nature of the traffic is. I'm with Spidey, your MAC is not changing .... unless you're changing it.

If you're using a SOHO firewall (or maybe even some software firewalls), you may have spoofed a MAC or something and it's conflicting somewhere.

Without a frame / packet trace, there'd be now way to tell.

FWIW

Scott