As a 32-bit OS, XP has a hard physical limit of 4GB of "address space"
that can be accessed directly. With some reserved for video buffers and
the like, 3.5GB of RAM the OS can use is quite normal.
The Core2 Quad CPUs I've worked with have been 64-bit capable, so you
*could* install a 64-bit version of Win7 to make use of more RAM.

There are (at least) two caveats:

1. There may not exist 64-bit drivers for all of your peripherals.
(You might consider a dual-boot arrangement if you are willing to
dedicate a drive partition to it....)
2. There's no obvious reason to assume that having access to your full
8GB of RAM will fix your playback problem. I don't see how it could
hurt, I'm just not certain it will help enough to justify the effort.

David Gillett

-------- Original Message --------
Subject: [PCBUILD] Jerky Bluray playback
From: Phillip Williams <[log in to unmask]>
Date: Mon, January 07, 2013 9:01 pm
To: [log in to unmask]

Greetings,

 To my latest build I added a bluray burner but when I attempted to
play a Bluray disc, it said I had to update to view content. After
about five nights of attempts, I finally successfully downloaded the
137mb update without losing my dial-up connection but when trying to
play the disc, the video is "jerky" with choppy sound. Tried two other
discs with the same results (DVDs play fine).

 While viewing Belarc Advisors info on my machine, I noticed only
about half of my ram was in use and research showed me that XP only
recognizes 3584 megabytes of ram (BUMMER!).

 Below are specs for my machine. I hope someone might be able to tell
me why I'm having troubles.

Mobo - ASUS P5G41T-M LX plus
CPU - Intel Core2 Quad (Q9550) @ 2.83GHz.
Bus clock - 333 megahertz
HD #1 - WD 80GB SATA (47.5 free) for OS and programs
HD #2 - WD 300GB SATA (220 free) for misc. files
Slot 1 DIMM - 4096 MB
Slot 2 DIMM - 4096 MB
Video - NVIDIA GeForce GT 520 1 gig
Display - ASUS VH242H 23.4 in. 1080p 5ms response (I tried different
screen size settings)
Sound card - Creative Audigy 2 ZS pro
Belarc and device manager list the Lite-on iHBS11204 (SATA) Bluray
burner as ATAPI iHBS 112 2 standard cd-rom
My player software is Cyberlink Power DVD 11

 Would having the extra, unusable, DIMM installed affect the
performance?
If I have to, I'll save up for a windows upgrade to 7 or 8 (which will
raise a whole new set of questions!) but I don't see why what I'm
running wouldn't play the Blurays properly.

 Thanks for any input,
 -Phil-

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