Quote from mgookin:
I reverse built a trading box. I started at the monitors and worked backwards. I ended up with the Asus P5K64WS mobo. It has four PCIeX16 slots and serveral more lesser x8, x1, etc. slots. It's marketed as a workstation mobo capable of 8 monitors, but with quad head gpu's it can run 16 monitors. And that's not even counting putting more GPU's in the lesser slots.
Watch your power supply loading as you pile on more GPU's. There are plenty of power supply calculators available online where you can tell it how many of what you have in your system.
Quote from mokwit:
Just to come back to this thread and S's "That's SUPPOSED to work" caveat.
Investigated the HP - it has 2xPCIEx16
Expansion slot
1 PCIe x8 (x4 electrical)
2 PCIe Gen2 x16
1 PCIe x1 (half-length)
3 PCI (full-height/length)
1 16-in-1 Media Card Reader (optional)
Just looking at that spec rather than the detailed spec I would have assumed that it would run a minimum of 2x 4 port PCIEX16 for 8 monitors, maybe 1 more two port in another slot. BUT they tell you in the spec that it will run 1xNVS450 OR 2x NVS 290 OR NVS 440 with 1xNVS290 - in other words max 6 monitors via PCIEx16 slots.
Fortunately the warnings given by S and others here made me check further.
Whether or not it will run 2xNVS 400 old PCI in PCI slots I have yet to determine. The lesser model I mentioned above apparently has no BIOS restriction on running graphics cards in PCI slot but HP sales are dubious as to whether its 250w power supply will support 2 cards (maybe they are thinking 256MB PCIE or 3d cards). Checking the wattage with calculator as suggested I would draw 235W - If anyone can tell me if that is enough excess that would be appreciated.
http://thermaltake.outervision.com/Power
Thanks to all for suggestions and caveats that have helped me to avoid an expensive mistake. I will probably build backwards from the monitor setup as suggested. Alternatively I can try the two NVS400's I bought for $50 each in the cheaper box and if it doesn't work it has enough spec to serve as a data crunching box that has to be replaced anyway.
Quote from Scataphagos:
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3. On the "wattage calculators", they always show maximum numbers.. such as would be drawn in the most powerful game or other such application. With workstation video cards in an trading environment, power usage will run around 180W or less.... so 350W is plenty.
Quote from mgookin:
Quantity of electrical connectors coming off the power supply is a consideration. Scat can probably tell you if you can put "Y" adapters in there to branch the 12v circuits and what happens to the wattage if it even is possible. Just a thought that came to mind; gotta make sure you can plug it all in.
Quote from rsi80:
The most recent NVIDIA driver supporting the NVS 400.
http://www.nvidia.com/object/winxp_2k_94.24_2.html
This driver doesn't work with the NVS 450 (or 290/295, for that matter).