Some clarification on my situation:
While I just built my new 6-core AMD 3.2 Ghz/16 Gb DDR3 Win7 64-bit system, I am not a professional editor and don't even own an HD TV. I edit stuff in 1920x180 .veg when I can, but most of my stuff is Net-platform, i.e. Flash or .WMV.
My video interface is still VGA due to needed extension chords to my dual 19" LCD monitor system -- both of which have digital I/0 as well as VGA out. So I have VGA out of them since the chords are VGA, then an VGA>digital adapters on the end of the chords since the card has digital in only.
But I don't play or need HD on my system-- with the exception of test renders of master .avi files before I downrez to Net format. There I see a definite out-of-sync thing going on in almost all players (Windows Media, VLC, etc.) But I usually do a WMV test too, and those play fine.
I don't have any problems with my video card as far as I know and drivers are current.
However...
Unlike XP 32-bit, I cannot use the forceware nVidia "Desktop Manger" that came with this older (circa 2005) video card -- a very useful app that allowed one to add a send-to-other-monitor button next to Min/Max/Close buttons at top of windows. nVidia has mostly discontinued this extra app but it seems that some newer cards have or may have it.
Reason I bring this up:
I was used to extending the taskbar across all monitors in XP + having that send-to feature, but neither are available in Win7. So I'm using a trialware version of Display Fusion that rectifies tha plus adding some other nice tweaks. USD $25, I have a week or so left to decide.
Which brings us to...
Do I
IF I can find one for around USD $100 that does have the "Desktop Manager" (another if), I wouldn't have to spend the $25 to get back the send-to feature. But I will probably still lose the across-monitors taskbar.
Yes, technically speaking, the newer cards are better, faster, of course. Mine has only 256 Mb. memory, most current cards have 1024 or 1 Gb. Other specs are probably also better, but again, I don't "do" HD and my interface is still VGA. And...
... working or rendering in Vegas (currently 8c) doesn't sink or swim according to GPU work as I understand it (Vegas uses CPU and RAM for those). I also don't know if higher specs would help work in Particleillusion 3 either.
Last but not least, I basically wiped out almost 40% of my entire financial funds rebuilding this computer (+/- USD $800 for it). I need to build my savings back up. I don't want to have to buy stuff I really, really,don't need.
Anyway, below are the specs of my card. Defined as "cheap mid-range" but has served me well so far.
Thanks for input.
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XFX version
Series: GeForce 6
GPU: NV41
Release Date: 2005-09-30
Interface: PCI-E x16
Core Clock: 325 MHz
Memory Clock: 350 MHz (700 DDR)
Memory Bandwidth: 22.4 GB/sec
Shader Operations: 2600 MOperations/sec
Pixel Fill Rate: 2600 MPixels/sec
Texture Fill Rate: 2600 MTexels/sec
Vertex Operations: 325 MVertices/sec
Framebuffer: 128,256,512 MB
Memory Type: DDR
Memory Bus Type: 64x4 (256 bit)
DirectX Compliance: 9.0c
OpenGL Compliance: 2.0
PS/VS Version: 3.0/3.0
Process: 130 nm
Fragment Pipelines: 8 (12)
Vertex Pipelines: 4 (6)
Texture Units: 8 (12)
Raster Operators 8