RAM Capacity

[rn5a]

My P4, 256 MB RAM m/c is dual booted with Win2K Pro & WinXP Pro. Today
I added another 256 MB RAM stick

When I had a look at the total RAM capacity (right-clicking My Computer
& selecting Properties), Win2K showed the total RAM to be 515 MB (the
capacity was shown in KB actually - 5,15,568 KB to be precise) whereas
WinXP showed the total RAM to be 504 MB (the capacity in WinXP was
shown in MB itself). Any idea why this difference of 11 MB between
Win2K & WinXP?

 

[Andrew Rossmann]

[This followup was posted to microsoft.public.win2000.general and a copy
was sent to the cited author.]

My P4, 256 MB RAM m/c is dual booted with Win2K Pro & WinXP Pro. Today
I added another 256 MB RAM stick

When I had a look at the total RAM capacity (right-clicking My Computer
& selecting Properties), Win2K showed the total RAM to be 515 MB (the
capacity was shown in KB actually - 5,15,568 KB to be precise) whereas
WinXP showed the total RAM to be 504 MB (the capacity in WinXP was
shown in MB itself). Any idea why this difference of 11 MB between
Win2K & WinXP?

It depends on just how 1M is defined.

Manufacturers are using 1M = 1,000,000
Computers use the binary equivelent = 1,048,576

512 * 1,048,576 = 536,870,912
515,568,000 / 1,048,576 = 491.684M
504 * 1,048,576 = 528,482,304

On my Win2K (I don't have XP), my 512M system shows Total Physical
Memory in Task Manager and Properties of 523568K (499.313M).

My guess is that Win2K is not including some memory. Also, your computer
appears to be reserving 8M for something, possibly for video?