Can't upgrade video card on HP a1540n

Please!!!

Everything seems to be in order, I can see why you're confused.
Do the other cards provide a display during boot up?

I get that first windows XP screen on all cards and then black-blank. I do know it boots all ther way up as I have the key strokes down for logging on and shutting down. I tried safe mode and I get the screen that shows the drivers as they load but then it will freeze there as well. while the computer keeps on booting up and I can log on as well. Since the GTS 250 used the same drivers for NVIDIA it shouldn't be that correct??

Anymore thoughts?

I might have said that you did not connect the cards correctly, but the 4670 needs no external power feed, and the card is booting properly so I'll discount that.
Have you tried different output connections? Sometimes this issue is down to the cable.
It is also possible that a BIOS update may be needed, check the HP site to see.

Do you think the cable may work on one and not the other? As it works with the 7300GT.
I'm pretty sure the BIOS was up to date since they hadn't updated it since 12/07 but I just did it again anyway. I'm probably going to try once more and that may well be it as I haven't been able to even get on in Safe Mode. It loads drivers on the screen and then the screen freezes with them on the screen but still boots up.

Have you ever tried booting in Safe Mode with VGA. I saw a post on another site that mentioned booting in safe mode with VGA. Do you think this will get me up and maybe able to load and remove drivers? I've never had to use that mode before and I'm unsure of it.

Thanks for the help again!

When Windows boots into Safe Mode it does not load any manufacturers drivers, only basic ones supplied by Microsoft so you should have no problems.
Once there it is possible to remove or install drivers as you see fit.

Tried once more yesterday, same results. Blank screen. I tried both VGA cable and DVI cables. Works fine on the 7300GT but nothing on the hd4670. This includes booting in Safe Mode and and with VGA. I even tried switching the DVI cable and monitor with another cable and monitor but still blank. When disconnecting the cable the monitor will say the signal is lost and go dark. Connect the cable and it brightens up again but no image. So I guess I'll forget the HD4670 and resign myself to the fact that the upgrade isn't going to happen.

Thanks for reading and sharing.