200W, mini-itx, what's the fastest system I can get?

JonJ678

JonJ678

JonJ678

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The summer is getting ever closer, and with it the very real threat that my electricity bill will no longer be included in my rent. Current computer is somewhere around 500W and spends most of its time folding, I've somehow convinced myself that the tenner a week in electricity justifies buying a low power computer. However I'm having considerable difficulty choosing a specification, so I'm hoping you kind folks can help me out.

I have a budget of around 150W for mini-itx motherboard, dual core cpu, ram and graphics only. Not gaming in the sense these boards usually take it, but I'll be annoyed if it's incapable of running age of empires or morrowind.

There are a few options that I've found, but none seem quite right.

1/ Atom + ion, comes easily under the wattage limit but is very slow
2/ i3 + intel H55 board, within wattage limits, fast.
3/ i3 + zotac H55 board, limited overclocking, infamous aftersales support and fair chance of mortality.
4/ E8400 + intel/zotac board, much as above two options
5/ i3 + dfi P55 board, great if I can get discrete graphics within budget
6/ J&W am2+ board, dual core amd. I very much like the board, but it's not very power efficient and I don't know anything about amd processors

Budget isn't too much of an issue, but I want this to be small, fast, quiet and reliable. It should be easily possible to get these four components for under 400. I'd appreciate any input you can offer, especially from those knowledgeable about the amd half of the field.

The mac mini offers a 2.26ghz c2d, 2gb ram, nvidia chipset for 500 quid. This is pretty poor value for money imo, so that's out unless they introduce i3 based ones in the near future.
 
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Well, if you're concerned about the power and not the budget, the i3 with h55 would be a good bet.

A second best bet would be tri-core energy efficent athlonII like the 405e or even the phenom 905e. I'm sure that the in-built HD4200 on 785boards would easily handle age of empires as well so that would save some vattage, temperature and money as well.
 
Low power means I can run it off a dc to dc board rather than an atx psu, which means one less fan. Similarly low power consumption means the fans I do need can turn slowly. Both are good things for what is basically a htpc.

i3 with h55 sounds spot on to me, except for the limited range of motherboards. Neither gigabyte nor asus appear to be planning any so I don't have much hope for an overclocking board aside from the zotac, which offers limited voltage adjustments to prevent it self destructing.

780/785 boards seem to be pretty much the same, the integrated HD4200 is rated as significantly better than the X4500 which, while rubbish, is just about good enough for my purposes. I'm trying to get my head around the energy efficient amd options, they seem to be the same as the normal parts but undervolted and underclocked which doesn't seem particularly useful.

Regarding the amd option, a comparison of the 720 and 705e tricores

From amd's website,
720 has a clock speed of 2.8GHz, a TDP of 95W, a vid range of 0.85-1.425V
705e has a clock speed of 2.5GHz, a TDP of 65W, a vid range of 0.8-1.25V
95*(2.5/2.8)=85W, so the clock speed reduction accounts for 10W
95*(1.25/1.425)*2=73W, so taking worst case scenarios for vid, dropping the voltage accounts for 22W

Google seems a little unsure whether the e version is an undervolted, underclocked normal version but it looks likely. There's not much in it as far as prices go, the 705e is slightly cheaper. I think an unlocked multiplier is probably more useful than a part binned for lower power consumption, so if I go for amd it seems I've found my processor.
 
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The x3 435 might be worth looking at as well.
About the e versions, I don't think they're just undervolted chips, they also seem to OC bit better on lower volts but you can give it a try, after all it's your choice. The e can be probably undervolted further too.

btw do you need matx board or full size is ok too?
 
Going to have to be mini-itx for various nonsensical reasons, which does make life somewhat more difficult.

A sensible choice would be an intel h55 board with an i3. A more exciting choice is a phenom tri core with J&W board, pricing seems similar. E8400 would be excellent if I could find an overclocking motherboard for it which doesn't have zotac written on it.
 
Ouch, I just had a bean count of how much I spent on my mini-ITX... somewhere around 620 it looks like. Wouldn't have thought it...

But if you ignore the SSD, 5570 and modding you'd get the core computer for well under 400 (I assume you will be looking at MM etc for some parts).

Zotac 9300 (not the one you didn't want) for 85 Klick*
E8400 for 63 Klick
4GB of DDR2 for 50 (27 each but try 50 for 2) Klick
Budget your HDD to say 50
Sugo SG05 for 75 inc slimline optical Klick* <- 300W PSU? could snaffle that out for a pico if you wanted.

Under 330 (plus you need a cpu cooler)


*Regarding the OC on the Zotac 9300, I haven't fiddled mine much, the multi is fixed, you can change the FSB and memory speed. Believe voltage can be changed too, haven't touched that, got 3400mhz on stock volts with my E8400 though.
 
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Nice one Hotwired, I've spent the last couple of hours digging through MM but still missed some of those. Cheers. There's a phenom 2 705e which also looks good.

I ran into that build a few days ago and couldn't think of anything worthy to say to it. I'm a bit worried for the health of your psu but peering carefully at the photos suggests it's not as starved for air as it first appears. Astonished that you haven't undervolted the processor, power consumption varies as the square of (voltage/vid) so just dropping it by a little bit will work wonders for your temperatures.

I'm struggling a bit with benchmarks and amd overclocking hints, but I think a J&W am2+ board with phenom 705e would be better than e8400 and the zotac board.
 
im currently working on a spec and like the j&w mobo for use with a amd chip tbc either the athlon or phenom. not sure yet which way togo. will be going for ssd and 4gb, win 7. hopefully pico psu & maybe custom case.:confused:

early days:p
 
I think the J&W 785G board search came up before, not sure we found anything, sellers seemed to be in Australia/Japan/China?

There is a 780G around but it uses the 3200 not the 4200 in the 785 I believe.
 
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Yeah, and even those options appear to have vanished now. I've got a couple of guys I can ask locally who stand a pretty good chance of sourcing one from China, if that fails the 780G board is readily available and probably the same thing really.

Their forums aren't letting me register weirdly, refusing to send me an activation email. I'll try them again in a few days.

Sounds like we're on the same page mymorph. Pico psu should be more than capable of this if there's no discrete graphics card, bit of a stretch if there is.
 
where theres a will there is a way:D
as for the cpu then, phenom x4 910e is pricey but keeps the 65watt limit of the mobo. be interested to now how my athlon x4 will perform by undervolting it and how much wattage that would use?? any1 now a formula? i did run a few tests early on by undervolting the cpu with some success before i went full steam ahead with overclocking and increasing the volts. unfortunalty my psu died a few days ago so until a replacement comes in the next day or so im unable to try it out again.
 
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Poverclock = Pstock * (frequency/stock frequency) * (voltage/stock voltage)^2

The power used at stock is ideally measured, but failing that the TDP (thermal design power) is normally taken as a worst case scenario. This is used in post 3 when wondering how the phenom 720 compares to the 705e.

If it's the MINIX™ 780G-SP128MB you have in mind I'm pretty certain it supports 95W watt processors but strongly recommends you use 65W ones to avoid massive overheating in a mini-itx case. Overclocking a 95W one without very good cooling on the mosfets is likely to kill it though. I've emailed their UK sales guy, so fingers crossed.

AMD
MINITX 780G-SP128MB for 105
Phenom 720BE for 100
4gb of sodimm ddr2 for 70

Intel
DFi Lanparty P55-T36 for 105
i3 530 for 90
4gb of ddr3 for 80

Basically nothing in it for price. A low profile, very weak dedicated graphics card is likely to outperform the HD3200 on the amd option anyway and should come under power budget, so inclined to go down that route instead. The zotac H55 board has surfaced at last, so choosing between that and the dfi is tricky.

Cancel my last. Turbo boost doesn't work on it, the azurewave wifi card they're using is rubbish, and their x16 pci-e slot is incapable of working with pci-e x1 cards. Zotac are dropped from the list again. Potential graphics card here, the 5450 in a passive, low profile version, drawing 20W under load. From 40 quid ish, depending on what type of ram.

DFI board is likely to kick the bucket when the processor draws around 125W. The 750 has a tdp of 95W, a maximum vid of 1.4V and a frequency of 2.66. Making a reasonable guess that 3ghz @ 1.2V is possible, this would be about 80W load. 20W for the gpu, a blatant guess of 30W for the motherboard, 10W pump, 15W hard drive, 5W fans is 160W. Not a whole lot of clearance from the pico, but it's within possible limits.
 
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Maybe change case instead and go for matx ? ;-) will make life a lot easier.
I'll see how low I can undervolt my 555 and see how much power it takes, might be a good buy as well.

i3 is probably better than the 720, it uses bit less power too I guess.

I'll do some undervolting tommorow evening and let you know, it's the same deneb chip as 9xx series and probably the 7xx so at least we'll have some idea of how low can it go with decent clocks.
 
Nah, I've already tried matx. It didn't go well, ended up moving to a full size case. It looks like mini-itx motherboards are capable of everything atx ones are, except for the single expansion slot of course. The main thing is whether I can get away with a pico psu or if I'll need to use an atx power supply. I think this means buying components, assembling them and testing before sorting out a case.

Definitely interested in your 555's results. Undervolted + overclocked is a brilliant combination. I'm a bit thrown by the triple/quad core power consumption being similar, it seems the dead/switched off core still uses some power.

Currently leaning towards the following specification, in the spirit of no half measures,
DFI Lanparty P55-T36, £105
i5 750, £160
4GB 1333mhz ddr3 £85
Sapphire 5450 £45
Pico psu £30
216W AC adapter £30
So £450 new. I'm not really in much of a hurry so should be able to get the processor and ram second hand bringing the price down to below 400. Criticism more than welcome.

Power consumption for the 750 here, suggests 130W load at stock or 110W undervolted, other hardware is an atx P55 intel board and a 9400gt. Pushing the limits of a 150W pico pretty hard (think it would be running over rated spec).
 
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what will it be used for btw? you not gonna fold on it do you?
Either way, a quad might be a good idea yes, even at low speeds.

I've seen another review where i5 showed around 147w tho.
Is that PSU rated 150max, or is it 200w 80%+ cert ?
If it's 150 max it might be hard to get that going really.

Anyways, I'll get you some multi core results tonight and we see how the power consumption scales over different number of cores and volts.
 
I was thinking of going out to get a power monitor to check what my computers draw.

Then I remembered I had something a little different but just as good, a Fluke T5-1000 voltage/current/continuity tester :)

By separating a live single wire from the rest in the power cord and putting it between the fork of the Fluke it can read the current passing through.

Its limitations are that it reads in 0.1A. Since that is then multiplied by 230V, have to consider that readings can be off by a few watts.

My 750 OC to 3.4 + 4890 stock:

Idle: 0.6-0.7A / 138-161W
3DMark06: 0.7-1.1A / 161-253W
Prime95 Blend: 1.0A / 230W
Furmark + Prime95: 1.4A / 322W

E8400 + 5570 stock:

Idle: 0.3A / 69W
3DMark06: 0.5A / 115W
Prime95 Blend: 0.4A / 92W
Furmark + Prime95: 0.6A / 138W

I'll see how dropping to stock and undervolting the 750 works out, if we knock off 44-60W for the 4890 on idle (depending on whose numbers you look at) could get a ballpark figure for what the 750 can run on.

Ok

Stock 750 (1.23125V):

Idle: 0.6A / 138W
Prime95 Blend: 0.9A / 207W

Undervolted to 1.1-1.5V (can't get a reading difference):

Idle: 0.6A / 138W
Prime95 Blend: 0.8A / 184W

Take into consideration there are also:

4x 120mm undervolted fans
1x 200mm undervolted fan
1x pump
2x 3.5" 7200rpm HDD

And knock off 44-60W for the 4890 on idle (then add a bit for your own GPU)


Will you feel the benefit of having so much of the wattage budget in the CPU? With a lower power CPU you could get a much better GPU in there.
 
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Fold on it? I imagine I'll end up doing so, certainly seems like something I'd do. It'll be replacing the missus laptop which is quite rubbish and now dying, so that when she gets back from a hard day trying to be a lawyer she has a computer that runs flawlessly to reduce anger. I want it to be quiet for the purposes of watching films and playing music, and also that noisy computers annoy me. 750 is probably a bad call.

That's a very, very good post Hotwired. With luck I should be able to go one better, I've borrowed a current clamp from uni. It'll tell me the current running through individual wires, accurate to about 3%. Given I know what voltage each line is at I'll then know what wattage each part is using. My psu is sleeved unfortunately, so I'm going to buy a set of extension leads and measure the current down every one of the internal cables of my computer. Fingers crossed I can get a complete set. Not that I've managed to work out how to use it yet mind.

Interesting point on cpu vs gpu wattage, need to have a think about that one.
 
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I'm measuring the current on my Fluke using its version of a current clamp - it actually has open ended jaws - but they only work on AC wires.

If your current clamp just reads from the jaws and also only reads AC (probably) you'll have to read from the power cord going to the PSU as I did.

I've split open the external sheathing on an old short extension cable to get a reading from one of the live wires. You'll probably have to do something similar.

On yet another note, PSU on my 750 is up to 85%, on the E8400 it's unknown. The Pico is higher efficiency (my inner cynic asks me if that includes the hot power brick feeding it) so readings might (or not) be higher than with a pico.
 
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Uhm... can't find my gear.
Any particular software that shows CPU power consumption or there isn't one?

---
on the bright side managed to undervolt the cpu @2.8ghz all the way down to 1.15 from 1.4v, so looks like the E chips are just undervolted ones after all? But then why would they OC better, strange stuff.
 
You can't really do it without hardware as your normal computer doesn't measure its own power consumption.

Comparison reviews tend to measure draw at the socket then show entire system power consumption idle/load/OC/UV etc.
 
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