Corsair CX400W for an ATX 1.X System?

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diggƒreak

Limp Gawd
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Jan 8, 2006
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I just scraped together some old parts that I'm going to use as a server.
I need to purchase an inexpensive power supply to along with it, and I'm noticing that the CX400W is quite popular these days.

However, the CX400W likes to deliver most of it's power on it's single 12V rail. I know that ATX 1.X PCs prefer most of the power on the 5V and 3.3V rail.

Will 130W max on the 5V and 3.3V be enough for these components? :

Athlon Socket A 950
2x 256MB DDR 2700
nVidia TNT2 32MB
PCI 2 Port SATA Controller (Silicon Image generic, purchased for this)
52X IDE CDROM drive
320GB Western Digial SATA HD
ECS K7S5A
80mm Fan

Some of the G-LUXON caps are already bulging on this board. What can a board death by bad caps take with it? I'd like some true stories here as I have a feeling the board is going to die, but I'd rather let it die and replace it than recap.
 
The general recommendation for non-12V AXP systems is 150-180W combined on the minor rails. I don't recommend that you use the CX400.
 
Zero82z said:
The general recommendation for non-12V AXP systems is 150-180W combined on the minor rails. I don't recommend that you use the CX400.
Click to expand...

Therein lies the problem. Most of those currently-available PSUs which put out a relatively large amount of power on the lesser-voltage rails are either very old designs that are unsuitable for use in a modern system or have total wattage ratings that are so high that it would normally be way overkill to use on such an older system which draws relatively little power from the crucial +12V rail. In some cases, one might have to purchase a 1000W+ PSU just to attain enough capacity on the +3.3V and +5V rails for a system that's originally designed to be used with a 400W ATX 1.3 PSU. Most of the current "good"-brand PSUs in the 650W to 100W range have a combined +3.3V/+5V capacity that's barely adequate for this legacy platform.

In this particular case, I would have retired that legacy system from regular use and bought an entirely new system. (Especially if the "good" PSU makers are no longer properly supporting such legacy platforms.)
 
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If you really want to reuse that PC, check out the Silverstone ST400 which does have 180W on the +3.3V and +5V rails:
$55 - Silverstone ST400 500
 
Just a thought, but you might also consider looking for a really good older power supply. It'd be used, obviously, but as long as it wasn't ancient it would still probably have some serviceable life left-especially if you get one made by a good company.

Recertified ATX1.x Enermax power supplies pop up on Newegg from time to time, or you could try to find one on ebay. You could also see what you can find on Ebay in the way of Zippy/Emacs units. A lot of their power supplies have a good amount of amperage on the +5v rail. This is $90, but it's good for 35a @ 12v. Zippy is a reputable company (despite the name), I'd be inclined to believe their labels. Alternatively, this is $50 and could be made to fit in a normal ATX case, depending on how much work you wanted to go to. It's rated for 33a @ 5v. It may not be ideal, but it may be a viable option.

Also, for what it's worth, I have a couple of 500w Ultra power supplies-not their modular ones, though-that are a couple of years old now (these ones, I believe) and one of them managed to power up an old Athlon XP2100+ T-Bred with a R9700 on an A7V266 when a Corsair VX550 I had wouldn't, so you might look into those. Don't misunderstand me, I'm not at all saying the Ultra is a decent unit-in fact, I'm pretty certain it's a complete POS-but for a really old system it might be what you need.
 
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Facepalm.

I crossposted this on another website, and simply based on that offhanded reply and reading the high praise from professional reviewers I decided to buy the CX400.

So now I'll be powering this system with a CX400. Let's say nothing fails;
Am I disproportionately putting stress on the 3.3/5V rails?
Will this affect the lifespan of the CX400?
Will I be able to add another hard drive in the future?

Replies to this thread started appearing right after I clicked "order"...
 
Let me put it to you this way. I had an older Athlon XP system and tried running it with an EA380 ( seasonic built ) and I could not OC the system at all and it had some issues at stock speeds. I put a generic Logisys 480w PSU on the system and I could OC the CPU and all stability issues went away. Would the EA380 have died? With full load on the +5v rail 24/7 probably. Did the machine run better with the El Cheap 'O' PSU? Hell yes it did.

You probably can expect an early death from your CX400. You are going to be powering a 52w CPU off your +5v rail, 4w on the +5v for the HD, 3 - 5w on the 5v for the Pci card, 10w+ on the 5v for the CD-rom and you'll prob lose another 20 on the 5v to the motherboard alone. Thats from the 100w total you have on the +5v rail.
 
diggƒreak;1035725914 said:
So now I'll be powering this system with a CX400. Let's say nothing fails;
Am I disproportionately putting stress on the 3.3/5V rails?
Will this affect the lifespan of the CX400?
Will I be able to add another hard drive in the future?
Click to expand...

Something will fail. You can't counter-assume that.
Yes
Yes
Yes if you want to kill the PSU/PC.
 
diggƒreak;1035725914 said:
Am I disproportionately putting stress on the 3.3/5V rails?
Will this affect the lifespan of the CX400?
Will I be able to add another hard drive in the future?
Click to expand...
Yes, yes, and yes. In fact, adding an HD would be beneficial since you'd be crossloading the PSU less. The CX400 is a group-regulated PSU and increasing the +12V load will improve +5V regulation.
 
Ok, based on three stern warnings I think I'll pull my Dad's PSU which is a cheap Raidmax ATX 1.3 (which has been powering an Athlon64 system for over a year), and give him the CX400.

It's a win-win.
 
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