This is my first post here and I have searched the forums so far for an answer to my question.  Although similar things have been asked before, they were some time ago and it appears that many cards are now not made anymore.

I have a Dell Optiplex GX270 desktop PC.  This has a low profile AGP slot and two full height PCI slots via a riser card.

I have a Samsung 1080 LCD TV and would like to install a video card and a sound card, into the GX270, that would let me connect them via SPDIF, internally or externally, and use the DVI port and a converter to HDMI.  This would then allow me to simply have one HDMI lead to carry the video and audio signal to the LCD TV if I have done my homework correctly.

I have read about nVidia Geforce cards having these internal connectors but cannot seem to find one that is AGP and low profile.  Can anyone suggest a model, or an alternative like ATI, and where I could get one please?

This will be my first media centre PC that I am building too, so please excuse me if I don't understand your responses fully.

Thanks

DVI+SPDIF -> HDMI converters cost hundreds of dollars.  The cheap $30 DVI->HDMI cables don't do audio.  Your best bet is to use the VGA or DVI input on your TV, then regular audio. 

Plus, AGP is not supported by any of the nice new graphics cards that do native HDMI with audio.  New cards use PCIe 16x slots.  The prefered card for HDMI with audio would be any AMD Radeon 3xxx or 4xxx.  The cheapest would be the Radeon 3450.  There are no Radeon 3xxx or 4xxx AGP cards. 

Thanks for the reply.  You are right about the PCIe cards.  I have found loads of them, but the GX270 is AGP.  Shame it's not a GX280 as they have PCIe and that would solve my problem.

I have read that lots of the old AGP cards used to have a little 2pin connector on the board so you could internally link your SPDIF out from your soundcard to it and the audio would be sent out the DVI port as well.  Mainly Geforce cards from what I have read.

http://www.hardwaresecrets.com/article/600/1

Although these again may have been PCIe as it states this for the Radeon based cards as you pointed out and is mentioned in the article.

I thought there must have been something AGP that did this at some point.  Anyone want to swap a GX270 for a GX280?

The tutorial that you link to is for PCIe nVidia cards.  HDMI wasn't even in use back in the AGP days, so there is no way that an AGP card could support using it.  The higher end geForce 8xxx, 9xxx, and 2xx series cards support HDMI audio through a pass-through, instead of a built in sound card. 

I found this which looks good

http://www.cableuniverse.co.uk/catalog/cables/DVI-Audio-to-HDMI-Converter.html

The only thing is that is needs another plug for the 5v power supply.  It's a shame it can't work off of the USB ports power in some way.

It all means more wires everywhere as well which is messy.  I've seen a manual switch type both that will do the same with 2 DVI devices but only standard L R sound inputs through to HMDI as well.  The bonus wit that is no power needed.

That means I only need a straight forward AGP low profile video card with as much video RAM as possible.  Am I right in thinking that I need 256MB to do a proper true 1080 HD display?  I also read somewhere that I'd need about 1GB RAM for this in the machine too.  Can anyone confirm this please?

USB supplies 500mA at 5v.  This thing takes 1000mA, which means that if you tried to plug it into a USB port by a power adapter, it might fry your mobo.  Just use the included plug. 

I've been in this situation a number of times. The best you are going to get is an ATI 9550SE. It will have DVI but not SPDIF audio. You can try an Nvidia 6200, but it will most likely crash resuming from S3 sleep. The ATI card will display standard definition TV on a 1080p display, but no chance of playing high definition content at that sort of resolution.
Actually Vista will be total pants on either of those graphics cards and do a rubbish job of deinterlacing. MCE 2005 will run really well on that box however, with for example the Nvidia Purevideo MPEG2 decoder.