If you would, provide us complete specs on your system. Makes it a little easier to determine what the problem could be. Also, do you know what temps the CPU and graphics card are at when this happens?
i just had this exact same problem on my computer. turns out i needed a new power supply - the one i had was insufficient. i had just added a new PCI card to the system and that pushed it over the edge. you don't list your specs but your symptoms sound just like mine.
I just disabled Hibernate on my pc and rebooted the pc...i just played a whole dream theater song without any freezing. broke a personal record hahaa
here are my specs:
OS Name Microsoft Windows XP Professional
Version 5.1.2600 Service Pack 2 Build 2600
OS Manufacturer Microsoft Corporation
System Name UNIMATRIX007
System Manufacturer VIA Technologies, Inc.
System Model KM400-8235
System Type X86-based PC
Processor x86 Family 6 Model 10 Stepping 0 AuthenticAMD ~1659 Mhz
BIOS Version/Date Phoenix Technologies, LTD 1004, 31/07/2003
SMBIOS Version 2.2
Windows Directory C:WINDOWS
System Directory C:WINDOWSsystem32
Boot Device DeviceHarddiskVolume1
Hardware Abstraction Layer Version = "5.1.2600.2180 (xpsp_sp2_rtm.040803-2158)"
User Name UNIMATRIX007Administrator
Time Zone GMT Standard Time
Total Physical Memory 1,152.00 MB
Available Physical Memory 743.63 MB
Total Virtual Memory 2.00 GB
Available Virtual Memory 1.96 GB
Page File Space 2.69 GB
Page File C agefile.sys
Name Creative EMU10K1 Audio Processor (WDM)
Manufacturer Creative Technology, Ltd.
PNP Device ID PCIVEN_1102&DEV_0002&SUBSYS_80271102&REV_083&61AAA01&0&40
I/O Port 0x0000C000-0x0000C01F
IRQ Channel IRQ 16
Driver c:windowssystem32driversctaud2k.sys (5.12.01.0252-1.31.0120, 817.92 KB (837,548 bytes), 12/02/2006 1:18 PM)
Name NVIDIA GeForce4 MX 420
PNP Device ID PCIVEN_10DE&DEV_0172&SUBSYS_87811462&REV_A34&1FEB96E4&0&0008
Adapter Type GeForce4 MX 420, NVIDIA compatible
Adapter Description NVIDIA GeForce4 MX 420
Adapter RAM 64.00 MB (67,108,864 bytes)
Installed Drivers nv4_disp.dll
Driver Version 126.96.36.19998
INF File oem5.inf (nv4 section)
Color Planes 1
Color Table Entries 4294967296
Resolution 1152 x 864 x 60 hertz
Memory Address 0xE0000000-0xE1FFFFFF
Memory Address 0xD8000000-0xDFFFFFFF
Memory Address 0xDC000000-0xDC07FFFF
IRQ Channel IRQ 16
I/O Port 0x000003B0-0x000003BB
I/O Port 0x000003C0-0x000003DF
Memory Address 0xA0000-0xBFFFF
Driver c:windowssystem32driversnv4_mini.sys (188.8.131.5298, 3.37 MB (3,536,768 bytes), 12/02/2006 12:33 PM)
Could be that oh so lovely bug that still seems to pop up with VIA chipsets and Sound Blaster sound cards.
Make sure your drivers are all updated. Make sure your motherboard is running the latest BIOS. If there is an option for V-Link 8x in your BIOS setup, disable it. I had to do that to fix sound stuttering issues with AOE III... I have an Asus A8V motherboard with a Sound Blaster Audigy 2 sound card.