What psu for my new htpc?

[saitrix]

Hi,

I have just bought some bits 2nd hand for a htpc I am building. I have bought laptop parts so they are running passive, with only a need for a case fan. So this means I need a silent/quiet psu, so I got thinking and decided a picopsu/electrodacus psu would be the way to go. One thing though is I am finding as I go up the wattage the price increases quickly, so what wattage should I go for?

T2350 CPU
2 sticks ddr2 sodimm
ATI HD4350
1x 3.5" hdd
bluray drive (maybe)

[Fire-Flare]

Hi,

I have just bought some bits 2nd hand for a htpc I am building. I have bought laptop parts so they are running passive, with only a need for a case fan. So this means I need a silent/quiet psu, so I got thinking and decided a picopsu/electrodacus psu would be the way to go. One thing though is I am finding as I go up the wattage the price increases quickly, so what wattage should I go for?

T2350 CPU
2 sticks ddr2 sodimm
ATI HD4350
1x 3.5" hdd
bluray drive (maybe)

Based on the information you gave, I wouldn't go less than 300 watts. Seasonic makes escellent quiet/silent power supplies in that range for under $50.

[saitrix]

I doubt a laptop CPU requires a 300w psu. Does anyone know what amount it will use roughly? I was looking at 90w picopsu. The 4350 seems to use 12w at idle and I only use it for films so I doubt it will go over 20w. Hard drive I don't think will go over 20w, so that just leaves the CPU and motherboard. Does a combined power usage of sub 50w sound correct?

[tim851]

Yeah, PicoPSU 90w should do it.

[saitrix]

Thanks, did more digging and was able to find someone with a similar setup running 36W at idle and 60W load, and I will be undervolted too. Though they didn't have the 4350 but that apparently is only ~15W.

[Fire-Flare]

Thanks, did more digging and was able to find someone with a similar setup running 36W at idle and 60W load, and I will be undervolted too. Though they didn't have the 4350 but that apparently is only ~15W.

My ATI 6870 reports it works at 20% load while watching DVDs.

3.5" hard drives draw 20-25 watts when starting up, a DVD drive might draw that much or more when reading/writing at full speed, and adding 50w for the video card means a 150 watt power supply should do it.