Gateway MX3228 can't see more than 512mb memory

Hi,

I'm a consultant and working on a customer's laptop.  It's a Gateway MX3228.

http://support.gateway.com/s/Mobile/Q106/MagicLC/1008831nv.shtml

It had a 512mb stick of PC4200 memory in it from the factory.  I replaced that with a Corsair 1GB stick of PC4200 memory.  Per docs I found online, this laptop only works with PC4200 memory.

I booted up, seems much quicker, thought I was done..but it only shows 512MB ram in Windows and in the BIOS.  I went into the BIOS and this option is not changeable.

I don't have the laptop with me now and I'm unsure if it's on the latest BIOS revision.  They didn't have a BIOS update available that could run from Windows and the laptop has no floppy drive and I had no blank CD's along, Grrr.

Has anyone else run into this?  I would think if the memory was incompatible it would just not boot up.

I tried to login to Gateway's support page and it says I already have an ID but my password doesn't work so I clicked the resend my password button and I never get the email.  Grrr again.  I'll have to use another email address I guess.

Thanks in advance for any help.

I checked and the laptop is on the 73.07 bios revision which is the latest version.

I also checked Corsair's site and the stick I bought is guaranteed compatible with this laptop model.

Hmm, I'll just wait to hear back from Corsair I guess.

I've never seen something like this, usually memory either works or doesn't.

I did check before I ordered and saw that only PC-4200 works in here, 5300 does not.