[Pc_Support] x-ray + laptop

[Justin M. Keyes]

Thanks Phil!


On Fri, 11 Mar 2005 18:35:30 -0500, Phil Barnett <philb at philb.us> wrote:
> On Friday 11 March 2005 04:03 pm, Justin M. Keyes wrote:
> > Hi guys,
> >
> > Is there a significant chance that an airport security x-ray may
> > corrupt a laptop's hard-drive or anything else?
> 
> Probably not. Way back when, they used much stronger magnetic fields to excite
> the x-ray tube and lots of people lost data on unprotected disks, such as
> floppy disks and even occasionally a hard drive. But about 20 years ago, they
> got much more efficient and the fields generated are very very small compared
> to what it takes to wipe data from a drive.
> 
> Technically, we are subject to cosmic forces every day that can cause this
> kind of damage. Chance change of molecules, cosmic radiation and other low
> energy phenomena can toggle bits in memory and can change bits in hard
> drives. For hard drives, we have ECC bits protecting data that decays.
> Expensive servers also have ECC memory to counter this effect.
> 
> It's difficult to say how much this effect has on average use, but chances are
> very high that at some point a crash has been due to this very low level
> stuff. Maybe even to someone you know...
>