Recommended me a PSU, pls.

Machupo

Machupo

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Working on a tiny (<10L) custom build and I'm not sure my venerable Nexus compact 630w unit is going to have enough juice to make it happen, so I'm looking for something a bit larger.

Here is what it needs to power:
- Z68itx w/ onboard ssd (mPCIe or mSATA), 2 ddr3 dimms, probably 3-4 USB devices.
- i7-2600k (heavy overclocking is a certainty)
- Radeon 6990 (overclocking is a possibility, but not required... AUSUM mode for sure)
- MCP 355
- 4x 140mm, 5.4 watt fans
- Some type of fanbus / system health object... possibly w/ capacitive touchscreen interface (screen no larger than 2" by 4")

Here's the characteristics I'm looking for:
- Minimal heat generation. This PSU will be de-boxed (so no fan) and rewired to the rail specification / lengths needed (so yeah, doesn't matter if it's modular or not... they're gettin' chopped off :D). It will be cooled by radiator fans which will be *just* on top of it (but will all be in "suck" mode, so no direct blowing on the PSU components).
- Minimal size. Looking for a unit where the PCB is less than (or equal to) 150mm in the "length" dimension... that is, not the dimensions that make up the ATX standard size, but the one that typically varies from 125mm (my nexus) to 180mm and more (1kw+ psus).
- Reliability. Obviously the warranty goes out the window the first day this thing is in my possession, so I'm looking for something that hopefully won't crap out (or in non-warranty-voiding situations, has a low RMA rate). This means the PSU needs to be happy running at this load (and other loads, say non-gaming mode) for variable periods of time (say 1 hour at the shortest to months at a time w/o being turned off).
- Price. I won't say that I don't care about the price, but it's the least of my worries. I want something that fits the bill, works well (no weird noises / bulges), and that I can trust. I'd like it if it was under $200, but if I can't find what I need in that price range, I'm amenable to other ideas.


Your suggestions / comments are greatly appreciated, and thanks in advance!
 
Won't those be a little short on power? I'm estimating 250w for the processor (based on plugging 5.5ghz and 1.6V into W=c*F*v²), 450w for 6990 in AUSUM mode, and ~50-100w for all the other randomness)... I was thinking that would put me into the 1kw PSU range to keep the load under 80% continuous.
 
The i7 2600k are surprisingly efficient, and they rarely pull more than 150 watts. I don't know what kind of formula you're using, but it definitely won't reach 200 watts. And the 6990 non-overclocked in AUSUM mode uses about 400 watts. 150+400+50 = 600 watts. Which the Kingwin Lazer has been proven capable of outputting, albeit at gold efficiency levels.

I wouldn't worry about keeping the system under 80% continuous. These power supplies are designed to handle 100% continuous. Since you wanted high efficiency, the Kingwin Lazer Platinum is the most efficient power supply you can get. There are none (at the moment) that can beat it.
 
Machupo said:
Won't those be a little short on power?
Click to expand...
If you run everything balls to the walls, probably. But you're not going to find a PSU that can handle that while still fitting into your space constraints. I suggested the next best thing.
Tsumi said:
I don't know what kind of formula you're using, but it definitely won't reach 200 watts.
Click to expand...
The formula he's using is more accurate than your estimates, given the correct initial conditions.
 
Tsumi said:
The i7 2600k are surprisingly efficient, and they rarely pull more than 150 watts. I don't know what kind of formula you're using, but it definitely won't reach 200 watts. And the 6990 non-overclocked in AUSUM mode uses about 400 watts. 150+400+50 = 600 watts. Which the Kingwin Lazer has been proven capable of outputting, albeit at gold efficiency levels.

I wouldn't worry about keeping the system under 80% continuous. These power supplies are designed to handle 100% continuous. Since you wanted high efficiency, the Kingwin Lazer Platinum is the most efficient power supply you can get. There are none (at the moment) that can beat it.
Click to expand...

I pulled the 250 from the formula in the previous post & Intel Ark data, the 450w came from a review I saw on the web of the 6990 @ 880mhz (which I thought was ausum mode... maybe i'll have to go read up on it again :)).

So I'm looking at about a 750w power draw (when the system is balls to the wall, but then I don't want to have to worry about overloading my PSU and killing the system, so might as well plan for the worst!). I guess I'd be o.k. w/ 100% load for 12-18 hours at a time since the system isn't going to be at max draw for the bulk of the time (when I'm not playing games), but that still leaves me looking for a slightly bigger PSU :(

I guess I can begin the build using my nexus 630w unit (which is only 120mm long on the inside) and monitor draw as I bump the processor freq/voltage (and keep the 6990 at stock 375w draw) and upgrade the PSU if necessary.


Zero82z said:
If you run everything balls to the walls, probably. But you're not going to find a PSU that can handle that while still fitting into your space constraints. I suggested the next best thing.
Click to expand...

Thank you :)

The reason I was thinking that something larger may fit is that IIRC (as an example), the Silverstone Strider 1kW modular psu is ~160mm long, but around 10mm of that internal length is occupied by modular connectors. If you look at pictures of the inside of the PSU, the PCB and components actually fit inside a 150mm length constraint (if you remove the modular business. The reason I was thinking this might be possible is from an initial google images search for the internal design of the Corsair AX850 which shows space beyond the PCB in the length dimension to accommodate the modular plugs.

Zero82z said:
The formula he's using is more accurate than your estimates, given the correct initial conditions.
Click to expand...

Yes, I extrapolated c from Intel Ark data (stock voltage / freq for the 2600k, well, an average stock voltage value of 1.25v since I notice that it differs from chip to chip), then computed the total processor consumption with the new f and v attributes :)


If anyone has a larger gold-certified PSU that they happen to have the cover off of, and could take a measurement of the PCB (or maximum length if there are overhanging components) that would be helpful too (you can PM me if you don't want to publicly void your warranty, lol :D)
 
Machupo said:
The reason I was thinking that something larger may fit is that IIRC (as an example), the Silverstone Strider 1kW modular psu is ~160mm long, but around 10mm of that internal length is occupied by modular connectors. If you look at pictures of the inside of the PSU, the PCB and components actually fit inside a 150mm length constraint (if you remove the modular business. The reason I was thinking this might be possible is from an initial google images search for the internal design of the Corsair AX850 which shows space beyond the PCB in the length dimension to accommodate the modular plugs.
Click to expand...
Some modular PSUs can't have the modular PCB removed. The AX850 is one of those.
 
nvm... got some more pics and can see why ;)
 
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