Onboard graphics and 3D shooters

[Bharath Ghanta]

The gma x4500 sucks at doom3 or sauerbraten. But it can play quake mods well at average settings. I dont know about the hd3200 but you can buy a graphics card like 9500gt. It does not consume much power and it can play all the games on your list at high settings.

[Duo Maxwell]

I'll probably pick a Gigabyte micro-ATX with AMD 780 plus a 45W Athlon.

From my own admittedly unscientific tests with libsensors, there's a noticeable difference in idling temperature with and without the PCI-E graphic card. Without the card, sensors often report single digit Core Temp's (8-9 C) on an AMD X2 2500 GHz. With the card it's always double digits (12+ C). This is totally anecdotal and I don't know how reliable as a metric of power consumption. But more heat means more power lost?

I'd recommend these AMD CPUs, though I'm not 100% on the Orleans core Atholon, as I don't know how well its extra L2 cache would hold up to the Brisbane derived Sparta core Semperon.

The 5400+ Black Edition is included since with that you can just drop the multiplier to as low as the cpu will boot to without having touching the ram, FSB or other components, allowing for a little more performance tweaking.

Why are you so worried though with the temps? A really good fanless cooler isn't that exspensive, If you need max coolness without noise, get something like a Scythe Orochi or Ninja Copper CPU cooler, an Enermax MODU82+ PSU and some 800RPM Scythe 120mm Fluid Bearing fans, as those parts will allow you to get away with ultra quiet operation if that's your goal.

So why exactly do you need to ke the temps so low? If low temps is your goal there are better ways to compromise such as liquid cooling.