Personally? I say dump the atom and grab yourself a nice cheap AMD duallie.
$40 for board.. (new price) and grab a REAL gpu for another $20... (last time i bought a cheap chepa GPU it was the 3450 with HDMI for $20 on the egg)
Always the used market as well.. although eBay will not be your friend on the cheap cheap
Gotta remember one thing... ratings for AMD chips are for top of family. And even then at stock they probably do not hit it. IE all processors in a family are rated for say 65W... that technically means... the highest one MIGHT hit 65W TDP..
Since no one has mastered the art of getting more heat from a substance than electricity provides... well commone sense
Ye olde 4200 chip is documented to run 42W at load despited having a 125W TDP rating.. simply because the 6000 was built on the same arch... and is a pig also. Dunno why AMD chose to adopt the methods of TDP rating they did...especially since Intel went the other route and said "we hope (fx fx fx) this will come in at XXX TDP" but it is what it is.
anything 700 series chipset.. (oh IGP on them is awesome too) I play games on a HD3200 ITX setup
older games.. but more flawless than my 4890 and newer games... soo
You said 150W max... EASILY doable with a AMD dualie.
If you do want to go intel, G41 is only option.. same power as the g31 but half the power bill. Personally I would not use ether (I have) g31 sucks for HDTV controls, and G41 does as well, although afterwards I heard they added DXVA... meh.. I doubt it works as well. PErsonally I dont like nVidia for that either.. it has these funky sliders to control resultion on an HDTV.. so that instead of fixing over/unerscan.. you just adjust the resolution .. which on my nviad GPU HTPC.. means my 720p LCD screen is running at about 638P kinda fucked up aint it?
People wonder why I am an ATI fanboy...
You are in my town now, and TBH, that is AMD country
(for the record, in an effort to stay current I have been running an ATOM setup, also been running 7 on 3 systems...2 of which are amd... i dont get the netbook thing since you can get a faster p3 laptop for much cheaper... for desktop? I would NEVER consider ATOM it cant even handle internet browsing IME)