With the success I had to in converting my two year old desktop into HTPC, I set out on a mission to convert an old Dell Dimension 4600 into a HTPC for my brother-in-law.
It just needed an graphics card with HDMI out (or so I thought). The motherboard has AGP slot, so we went out and purchased a graphics card with AGP slot, HIS Radeon HD 4350 512 MB (64bit) DDR3 HDMI AGP card. Since the power requirement for this card is 300Watts power supply, so we also got a 350W power supply.
Every thing was plugged in. Switched on the power and there is no display on the monitor. So the first sense was what if the new graphics card is bad ? So we put the old graphics card back in and powered on and display is working fine. Switched back to the new graphics card, no display, no bios display during power on boot cycle.
Started research online as to what could be the problem. We stumbled upon the review on amzon. It seems the old Intel 865G motherboard that is present in the Dell Dimension 4600 does not understand the new DDR3 cards (or DDR2). The next morning we called the technical support for HIS and they confirmed the same.
The only solution is to find out if motherboard manufacturer or the system manufacturer has an update for the BIOS recognize DDR2/DDR3 memory cards. So downloaded the latest BIOS update from Dell site and tried it and no luck. The last BIOS update was in Sep 2004, so there is no chance of it supporting the latest memory. So you need to find a graphics card that uses DDR (pc3200) memory in the graphics card with HDMI out. And we could not find any.
With that we gave up. So before we take up the conversion of old desktops to HTPC, just verify the compatibility of the components.