Max memory in Sony Vaio PCG-Z505R[X] ?

Archived from groups: comp.sys.laptops,alt.comp.hardware (More info?)

"Andrew Gabriel" <andrew@cucumber.demon.co.uk> wrote in message
news:42fe28b3$0$38037$5a6aecb4@news.aaisp.net.uk...
> I've got an old PCG-Z505RX with 128M RAM, which is 64M on motherboard
> and 64M SODIMM. The instructions say it can take 192M max by swapping
> out the extra 64M SODIMM for a 128M SODIMM.
> Does anyone know if I could put a 256M SODIMM in it and get even more
> memory? I'm wondering if the instructions simply predate 256M SODIMMs,
> or if there's a limit in the Vaio itself, either the chipset or the
> motherboard, which would prevent a 256M SODIMM either working or
> providing its full capacity to the laptop?
>
> --
> Andrew Gabriel

I'm guessing here but it probably has more to do with the motherboard not
being able to handle the higher density chips on a 256m sodimm than the
machine predating the release of the 256 stick. This is quite common in the
desktop machines from 5 or 6 years ago. You could install a single sided
256mb sdram stick and the machine would only see 128mb but if you got a
double sided 256 stick it would see all of it. Have you taken the machine
apart to see if the onboard 64mb is not replaceable? Typically it's just
another sodimm that is hidden from view.
Obviously the only way to know for sure is try it, or hopefully someone here
may have already done that and will answer.