Hi everyone
For starters here is my PC Vostro 400 from Dell
Intel Core 2 Qhad Q6600(2.4GHz, 8mb,L2cache, 1066Fsb)
WindowsXP
2Gb DualChannel DDR2SDRAM 800 Mhz, 2 DIMMs
320 Gb serial ATA Hard Drive 7200 RPM

The 256 MB NVIDIA GeForce 8600 GT was causing issues (blue screen and fuzzy) and as per suggestions, I replaced it with XFX Radeon HD 6670.

Opened PC in safe mode & removed VGA drivers from device manager;and proceeded to install with CD. Before even staring, PC wanted to try to add new hardware but does not recognize which model it is. Rebooted again in safe mode and tried with CD but tells me to check www.xfxforce.com for drivers. Did this and downloaded drivers for WinXP system; when catalyst tries to install drivers message reads "failed to load detection driver" and now I am stuck.

Note that the fuzzy screen has been CLEARED up and I did double check to VERIFY that card is attached to motherboard. Had one suggestion to remove 6670 card and reattach Nvidia card and then remove all drivers before trying again with 6670; sadly, I have thrown out the NVIdia card.

Also, when I run a search for any files with 'nvidia', I find quite a few; should I delete this or do they have nothing to do with the operations.

When I boot PC in normal mode , this blue screen pops up:
STOP: 0x000000FC (0xB7F47C40, 0x2A7B5963, 0xB747B78, 0x00000001)

Unsure what to try next and in what sequence.

Didn't you recieve a Driver CD with the 6670 ? ?
If not i would try the XFX site for the proper drivers...I'd grab the drivers from ATI's website.0xFC - Is when the computer is instructed to execute non-executable memory space.

Did the machine boot OK in normal mode to BEGIN with when the card was first installed? If so I would reccommend doing a system restore to try to go back far ENOUGH to get the machine booting in normal mode again, which should ALLOW you to install the drivers correctly.No, every time I have tried booting in Normal mode, the blue screen comes out.

When I try installing with CD, it tells me to go to website.
Website allows me to download drivers for WinXP system; then, when catalyst tries to install drivers message reads "failed to load detection driver" and I cannot get anywhere.