[rescue] Sun Ultra 60> 2 Gb Memory ?

[Chris Quayle]

>
> Today's Topics:
>
>     1. Re: Sun Ultra 60>  2 Gb Memory ? (Ethan Hawke)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sat, 7 May 2022 13:11:02 +1000
> From: Ethan Hawke<ehawk at ember.systems>
> To: rescue at sunhelp.org
> Subject: Re: [rescue] Sun Ultra 60>  2 Gb Memory ?
> Message-ID:<1adcbcd9-6b24-fb4c-0834-a79f5ebc42be at ember.systems>
> Content-Type: text/plain; charset="utf-8"; Format="flowed"
>
> The DSC (Memory Controller in the U2) can only address up to 2GB of
> total memory, I would guess that 256MB SIMMs would be treated as 128MB
> as the extra addressing pins would probably be grounded.
>
> Cheers,
> Ethan


>
> On 5/7/22 04:22, Mark M wrote:
>> There were 256MB Dimms of that type (200pin), but were only ever
>> certified for U80 and E450s.
>>
>> The handbook memory compatibility matrix actually notes that they do
>> work in e60s but there's an obp bank limit of .5G.
>>
>> All that said, I've never tried, but would, if my machines weren't in
>> storage at the moment.
>>
>> -mark
>>

Thanks for the replies. If you think that 2Gb is a signed 32 bit number,
the 2Gb limit would make sense, but if 256 works in a U80, I wonder if
the obp firmware could be hacked to allow more than 0.5Gb per bank ?.
Don't have a U80, but it follows on from the U60, perhaps just an
upgrade ?. Ideal would be if the MB is the same ohysical size, but not
exactly thick on the ground.

May just buy 4 x 256 dimms to see what obp thinks it's looking at...

Chris