What about firewire connectivity? Is your Onyx daisychained to other firewire devices or directly connected to the mobo firewire? the reason I asked for detailed info is because knowing even what model of mobo you have is important. Identifying the chipset helps determine possible hardware conflicts. Even having a relatively powerful video card has been known to cause havoc with DAWs.
The 3 Onyx are directly connected to the computer, not daisy chained.
Operating System:Windows XP Professional Service Pack 3 (build 2600)
Install Language: English (United States)
System Locale: English (United States)
Processor:2.67 gigahertz Intel Core2 Quad Q9450
64 kilobyte primary memory cache
12288 kilobyte secondary memory cache
64-bit ready
Multi-core (4 total)
Not hyper-threaded
Drives:1400.30 Gigabytes Usable Hard Drive Capacity
944.91 Gigabytes Hard Drive Free Space
HL-DT-ST DVDRAM GSA-H10N [CD-ROM drive]
HP DVD Writer 1040d [CD-ROM drive]
NKRIFO V0L6FKH SCSI CdRom Device [CD-ROM drive]
3.5" format removeable media [Floppy drive]
ST31000340AS [Hard drive] (1000.20 GB) -- drive 1, SMART Status: Healthy
ST3200827AS [Hard drive] (200.05 GB) -- drive 0, SMART Status: Healthy
ST3200827AS [Hard drive] (200.05 GB) -- drive 2, s/n 4ND3NG3A, rev 3.AAH, SMART Status: Healthy
Main Circuit Board:Board: ASUSTeK Computer INC. P5Q-EM Rev 1.xx
Serial Number: MS1C88B82Q02489
Bus Clock: 333 megahertz
BIOS: American Megatrends Inc. 0202 07/25/2008
Memory Modules: 3294 Megabytes Usable Installed Memory
Slot 'DIMM0' has 2048 MB (serial number SerNum00)
Slot 'DIMM1' has 2048 MB (serial number SerNum01)
Slot 'DIMM2' is Empty
Slot 'DIMM3' is Empty
Local Drive Volumes: c: (NTFS on drive 0) 41.94 GB 3.13 GB free
d: (NTFS on drive 1) 1000.20 GB 688.72 GB free
e: (NTFS on drive 0) 158.11 GB 97.16 GB free
g: (NTFS on drive 2) 200.05 GB 155.90 GB free
Controllers:Standard floppy disk controller
Primary IDE Channel [Controller] (3x)
Secondary IDE Channel [Controller] (3x)
Standard Dual Channel PCI IDE Controller (3x)
Bus Adapters:APP7SS8H IDE Controller
Standard Enhanced PCI to USB Host Controller (2x)
Standard Universal PCI to USB Host Controller (6x)
Other Devices: OHCI Compliant IEEE 1394 Host Controller
VIA OHCI Compliant IEEE 1394 Host Controller
61883 Class Bus Device (3x)
AVC Device (3x)
CyberPower Battery Backup
USB Human Interface Device (2x)
Standard 101/102-Key or Microsoft Natural PS/2 Keyboard
HID-compliant mouse
USB Protection Device
USB Root Hub (8x)
*will update information tomorrow*