Dell Dimension 8300 with Geforce 7800GS OC

[mrtosh]

I have an old Dell Dimension 8300 in which the original Radeon 9800Pro had burned out. I purchased a BFG Geforce 7800GS OC and a BFG 450watt PSU with which to run it. I have installed the new PSU and it works fine but when I connect the 7800GS, the computer starts to boot but I get no picture to the monitor. I suspect that it is an incompatibility issue between the PC and the graphics card, does anyone have any suggestions as to how it can be resolved, BFG tech support have been quite unhelpful, they tried to convince me that I needed to disable the embedded display adapter in the device manager, but it only shows whatever is connected through the AGP slot, no embedded display adapter is present.

 

[Tmagic650]

These old Dells were very picky about what hardware is installed in them. Does this 8300 have a VGA connector on the motherboard near the Mouse/Keyboard connectors? If so, it does have on-board video. If the old 9800 was AGP, the motherboard video settings should be ok. Check to make sure that you have connected the power supply to the 7800 if it has a power connector on it... Then try another video card. The BFG might be defective

 

[mrtosh]

Thanks for the incredibly rapid reply. No VGA connector on the motherboard, I've tried the card in another computer and it works fine. Is it possible that the BFG GS-450 PSU I installed to run it doesn't supply enough current, 18A across each of the two 12V rails?

 

[Tmagic650]

So the BFG card doesn't need the extra power supply connection? The power supply should be good enough. It is possible that the old 9800pro fried the Dells AGP connector. Try a PCI video card next

 

[mrtosh]

Yes, The BFG 7800GS does require direct connection to the power supply, which I have done. I have it connected, the fan comes on, the blue LED's light up, but my monitor says no signal. I've been running an old AGP card since I fried the 9800 Pro, a hideously old and dated card just to allow me to use the computer, but it works so there's nothing wrong with the AGP slot.

 

[Tmagic650]

So the BFG card is simply not compatible with the Dell motherboard. Did you try removing the Radeon drivers before installing the Nvidia card

 

[mrtosh]

That's something I haven't tried. I'll give it a go this evening and see what happens. Thanks for all your help on this, I'll let you know how it goes.

 

[mrtosh]

Problem Solved

BFG tech support were really helpful, surprisingly. Once I explained to them specifically what the problem was, they generated an RMA number for me. I then shipped the card back to them and they re-flashed the bios on the videocard to an older version, compatible with my computer. It now works perfectly.