Working within power limits

Grimgoth

Grimgoth

Grimgoth

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Thinking of moving down in size from a mATX to an ITX with that nice zotac mobo. However, I notice that most of them cases don't take a standard ATX power supply; I think the In Win cases that OcUK have are with a mATX 120 W power supply. I've had the occasion to try and source one of these, and I think they go up to about 270 W.
Therefore it is now quite essential that we work within a set amount of power, and now my question is:
How do I find out (easily) what kind of power each component needs?
 
Best way is pretty much to look at reviews and other people's real world readings, Outervision is pretty useless for mITX. I just spec'd up my rig without GPU and it's telling me 183W for a stock E5200, 1 SATA HDD, a DVD burner, a single case fan and 3 USB devices all @ 90% load. There is no way those figures are anywhere near correct, i'd say a good 100W out.
 
tell us what you're planning and we'll do our bests to give you an idea of power consumption. It really depends on the platform you are using - atom, intel mobile, socket 775... you get the idea.
 
Ive got the Zotac board and an E6300 equivalent Xeon and using the onboard gpu it maxes out at 81w using one of those plug in energy readers, gaming is around 68w and windows idle is 38w.
 
There's a Lian-Li case for ITX that takes a full size ATX PSU - sadly the size suffers for it.

The Silverstone Sugo SG05 has a 300W PSU with reportedly enough grunt to take a 4870 with a quad core, might be worth getting one of those.
 
That calculators always been a country mile off.

My ITX C2D system draws no more than 80 watts at full load and yet that calculator shows it to be 160 watts. Double???!!! :confused:

gt
 
Not the biggest surprise that a PSU maker creates a calculator which recommends you buy a bigger (and more expensive) PSU than you actually need.

What's the full spec of your build gt?
 
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Hmm, thanks for the calc mr.white, at least its conservative ballpark estimate... it wants 350W for the system i was thinking of:
a zotac mITX with wi-fi, a q6600 energy efficient 95W SLACR (whats the normal quad core rating?), two sticks of RAM, 1 7200rpm notebook drive (or a 32gb ssd), a blu-ray disc player (do the notebook ones draw less power?) one case fan (i guess) and an external hard disk (but thats going to have its own power, so who cares)

edit: do you think the 120 W in win cases that OcUK have is going to be enough?
 
gt_junkie said:
e7200, flycreek mobo, 4gb DDR2, laptop hdd and BR drive.

Runs nicely. Performance feels like a full sized desktop.

gt
Click to expand...
I'm looking at building a system with one of the In-Win cases and the Zotac 9300-itx wifi mobo, but I'm wondering if I can get away with adding a graphics card instead of relying on the on-board GPU.
It's hard to know if the PSU is up to it, I wish manufacturers would be more aware of this and include power consumption with the specs on their components.
 
120W would at best get you a low end graphics card. If you've looked at benchmarks of the GF9300, it's not a bad IGP at all.

Even at gaming it has a mediocum of punch, and can do hardware accelerating of all the major codecs.

So personally, if you weren't looking to put in at least a 4600 series, I don't think it would be worth it over the IGP. And if you are, it's going to be close to the PSU limits.
 
I need to stop thinking about graphical power really, the only games I'd play on it would be classics via MAME. I've always been a 'bigger, faster, more fps' kinda guy, so this downgrade is rather counter-intuitive!

I'd be interested to know how far I could OC my E6300 CPU on it though, even with a low amount of graphical power, I'd still like to have a punchy CPU.
 
I think you'll be pushing your luck to run a Q6600 with the rest of your specs on a 120W psu. If you ever give that enough calculations to get near 100% useage on each core you'll be very close if not over the 120 W and almost certainly over the suggested amount for a 120W psu - depends on each, but suggested not to put much over 95 watts through it...

If you use a Q8200 you might be a little more lucky as they are the 45nm core which use 65W
 
right, now i am a bit confused-
as i understand it the 95W and 65W ratings of those chips are the TDP ratings- what amount of heat the cpu generates and your cooler needs to get rid of; I thought both would require roughly the same amount of volts/juice to keep going, and that the 65 W ones were just more efficient in the amount of heat generated due to using a smaller manufacturing process.
 
Grimgoth said:
Hmm, thanks for the calc mr.white, at least its conservative ballpark estimate... it wants 350W for the system i was thinking of:
a zotac mITX with wi-fi, a q6600 energy efficient 95W SLACR (whats the normal quad core rating?), two sticks of RAM, 1 7200rpm notebook drive (or a 32gb ssd), a blu-ray disc player (do the notebook ones draw less power?) one case fan (i guess) and an external hard disk (but thats going to have its own power, so who cares)

edit: do you think the 120 W in win cases that OcUK have is going to be enough?
Click to expand...

http://www.silentpcreview.com/article943-page5.html

Similar set-up, but with an E7200 rather than a Q6600. 65W load :) I'd think you'll be OK, though i wouldn't put much more on the PSU. To be safe see if you can find a review that tests the power draw of both chips and add the difference to this system's 65W. I know i've seen one, think it was on Tom's Hardware.
 
That calculator is well off. I have a meter which says my shuttle is using 180w full load and the site says I need a 547w PSU, only have a 250w shuttle one lol, worked fine for nearly a year now.
 
satchef1 said:
Best way is pretty much to look at reviews and other people's real world readings, Outervision is pretty useless for mITX. I just spec'd up my rig without GPU and it's telling me 183W for a stock E5200, 1 SATA HDD, a DVD burner, a single case fan and 3 USB devices all @ 90% load. There is no way those figures are anywhere near correct, i'd say a good 100W out.
Click to expand...

No way is that going to be 183 watts. Under full load it be around 80 watts.

Edit: doh, that is exactly what you were saying.
 
Guardsmon said:
If you use a Q8200 you might be a little more lucky as they are the 45nm core which use 65W
Click to expand...

Hmm, where did you find that a Q8200 uses 65W? I've done some digging and it looks like there are supposed to be energy efficient versions of all the quad processors coming out (with an S suffix, so Q8200S, Q9550S, etc), that are rated at 65W, but the normal versions of the Q8** series all are 95W, as far as I can see...
 
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