yup, more computing HP needed. I have MaskPro on my Win 7 64 bit system (I5-750), 8 GB, and it purrs. Don't forget that your video card will greatly affect how your system is able to paint the image on your screen. I got 8 MB on my card.
Adobe Photoshop Version: 11.0.2 (11.0.2x20100514 [20100514.r.591 2010/05/14:02:00:00 cutoff; r branch])
Operating System: Windows NT
Version: 6.1
System architecture: Intel CPU Family:6, Model:14, Stepping:5 with MMX, SSE Integer, SSE FP, SSE2
Physical processor count: 4
Processor speed: 2660 MHz
Video Card Vendor: NVIDIA Corporation
Video Card Renderer: GeForce GTS 240/PCI/SSE2
OpenGL Drawing: Enabled.
Video Card: NVIDIA GeForce GTS 240
Video Mode: 1920 x 1080 x 4294967296 colors
Video Card Driver: nvd3dumx.dll,nvwgf2umx.dll,nvwgf2umx.dll,nvd3dum,nvwgf2um,nvwgf2um
Driver Version: 8.17.11.9745
Built-in memory: 8151 MB
Free memory: 6462 MB
Memory available to Photoshop: 3255 MB
Memory used by Photoshop: 60 %
Image cache levels: 4
Serial number: 92628392251104103208
Application folder: C:\Program Files (x86)\Adobe\Adobe Photoshop CS4\
Temporary file path: C:\Users\Dad\AppData\Local\Temp\
Photoshop scratch has async I/O enabled
Scratch volume(s):
Startup, 916.8G, 779.7G free
Primary Plug-ins folder: C:\Program Files (x86)\Adobe\Adobe Photoshop CS4\Plug-ins\
Additional Plug-ins folder: not set