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Archive for December 2012

Using the PAE switch to enable 4GB RAM in Windows Server 2003 SP2

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In theory, the more recent versions of 32 bit Windows all support up to 4GB of memory and some support additional memory beyond 4GB when the Physical Address Extension (PAE) switch is enabled in boot.ini.

I’ve just upgraded a Windows Server 2003 SP2 server from 2GB to 4GB and so was disappointed to find that Windows only recognised 3GB. A few blog posts suggested that although the PAE switch is intended to enable use of memory above 4GB it seems to affect how Windows handles memory in the 3-4GB range too.

It’s an easy enough change to try. Just add /PAE to the end of the parameters in boot.ini:

[boot loader]
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows Server 2003, Standard" /noexecute=optout /fastdetect /PAE

It worked in this case – after a reboot Windows reported 4GB of physical memory.

Written by Sea Monkey

December 14, 2012 at 8:00 pm

Posted in Environments, Hardware

Tagged with ,

Abraham Wald

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Dr Aoife McLysaght, Associate Professor of Genetics, at Trinity College, Dublin was interviewed by Eddie Mair on the Radio 4’s PM programme on Thursday 6th December 2012 about her work on Evolutionary Genetics.

Dr McLysaght used the work of Abraham Wald as an example to illustrate how a seeming lack of first hand evidence can sometimes be used to make useful deductions.

“There’s a core priciple of evolutionary genetics in terms of what the comparisons can tell you and this World War 2 analogy explains it. So, there was this statistician, Abraham Wald, who in World War 2 was asked to come in and help the air force how to decide to use their limited resources, in terms of metal, to reinforce the planes so that they could reinforce the vulnerable parts of the planes. And what he set about doing was looking for the parts of the planes returning from the battlefield that didn’t have any bullet holes in them. This seemed counterintuitive, why was he looking at the parts of the planes that didn’t have bullet holes in them ? This is because any planes that were hit in that region didn’t return from the battlefield because they were shot down and you have the same kind of logic in evolutionary analysis because when I’m doing these gene comparisons, comparing human DNA to chimp and gorilla and out to fish, when we look for regions of DNA that haven’t changed, it’s not because it never happened, it’s not because the bullet never hit, it’s because they didn’t return from battle in terms of natural selection so these regions of DNA that we don’t observe changes in, are regions where when the change happens it’s really devastating in terms of what the normal, correct, function of that gene could be.”

Wald’s report “A Method Of Estimating Plane Vulnerability Based On Damage Of Survivors” is availableĀ at https://www.cna.org/sites/default/files/research/0204320000.pdf.

Written by Sea Monkey

December 11, 2012 at 8:00 pm

Posted in General

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