Re: Encrypted Swap

Gerhard Mack (gmack@innerfire.net)
Fri, 17 Aug 2001 09:34:56 -0700 (PDT)


On Fri, 17 Aug 2001, Holger Lubitz wrote:

> "Richard B. Johnson" proclaimed:
>
> > Errrm no. All BIOS that anybody would use write all memory found when
> > initializing the SDRAM controller. They need to because nothing,
> > refresh, precharge, (or if you've got it, parity/crc) will work
> > until every cell is exercised. A "warm-boot" is different. However,
> > if you hit the reset or the power switch, nothing in RAM survives.
>
> Then this may have changed with SDRAM. However, back in my Amiga days it
> was pretty common to just reset the machine and rip whatever was left in
> the memory (DRAM). If memory serves me right, some people put in reset
> protection (by pointing the reset vector to some code that cleared the
> memory), which could be fooled by hardware reset or power cycling.
>

My Apple IIc's manual recommended waiting 15 seconds before turning the
machine back on in order to wait for the memory to clear. I wonder how
long SDRAM lasts if actually removed instead of letting the BIOS clear it
on boot.

Gerhard

--
Gerhard Mack

gmack@innerfire.net

<>< As a computer I find your faith in technology amusing.

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