I need a new budget PSU. Any recommendations?



[QUOTE=Ibex;2084522]This article may be of interest to anyone who wants to find out the actual manufacturer of their power supply -

How to Discover Your Power Supply Real Manufacturer http://www.hardwaresecrets.com/article/370[/QUOTE]
Many of the private labels (Antec, Corsair, OCZ, etc) are paying UL to list their names behind the “E” numbers, so this doesn’t work as well as it used to.
The top reviewers will take the PS apart and identify it that way.
Sometimes the ODM will have a mark on the PCB or the PS will have a known configuration unique to a particular ODM.


I have made an important discovery - my case has a ledge for the power supply to sit on, and at about 60mm deep it will partially obstruct a large fan on the underside of the power supply. The shelf cannot be removed (but I may be able to bend it down to give 5-10 millimeters clearance).

The only PSU on the shortlist without a large fan on the underside is the Antec Earthwatts 380W, so decision made? Not yet.

Older computers rely much more on the 3.3V & 5V rails than current computers and I have been concerned from the begining that most current power supplies are too weak on the 3.3V & 5V rails.

I haven’t been able to find the information that I need to calculate the load for the 3.3V & 5V rails properly (despite spending the weekend looking through every relevant technical document I could find on the internet), but by making reasonable assumptions and filling in some gaps using an example computer configuration in an AMD technical document I have come up with an estimate of around 150W. Most of this load is on the 5V rail (I estimate 100-120W).

[B][I]EDIT : This figures are based on the CPU being run from the 5V rail. I belive this to be the case but I have been unable to find confirmation (enquiries are ongoing). If the CPU is being run from the 12V rail then 45-51W can be deducted from the totals and so the following would not apply.[/I][/B]

The Antec 380W Earthwatts specification is 20A/+3.3V and 20A/+5V, but they don’t give the all important combined maximum. But it won’t be any higher than the 500W Earthwatts which has a combined 3.3V+5V maximum of only 136W (and 24A on each). And the excellent Corsair VX450W that was looking like the best option earlier has a combined 3.3V+5V maximum of only 130W (20A each). In fact the only PSU on the list that appears to have have adequate 3.3V & 5V rails is the FSP 400W ATX-400PNF which has a combined 3.3V+5V maximum of 150W and a 5V rail rated at 28A. But this PSU has a large fan that would be partially blocked by the shelf. There are even 500W to 700W PSUs that can’t supply enough 3.3V+5V power.

For comparison the specification of my current FSP 250W PSU (model FSP250-61GN(A)) is 15A/+3.3V, 25A/+5V, 7A/+12V and combined 3.3V+5V maximum of 150W. I didn’t have this information earlier because the label was partially covered by that annoying shelf and I had to remove the PSU to read it.

This makes me think that a) my estimate is about right, and b) I could really do with a PSU that can supply a bit more power on the 3.3V & 5V rails combined. Although I am giving my PSU a high load the 3.3V & 5V voltages are well within the ATX specification (3.26V & 4.95V) and just as importantly stable. The 12V voltage has always been low (11.80V) even with all drives disconnected, but this is still well within specification and stable. But I still wish to replace my current PSU as it is certainly noisier (and therefore probably running hotter) than it used to be.


Greetings Ibex,
Your research is quite impressive !
I wouldn’t worry about a 120mm fan being partially blocked by a rail, unless it was 50% blocked or something like that.

Now don’t laugh, but one PS mfr that comes to mind with regards to legacy power (strong 3.3v/5v) is Sparkle (SPI).
That brand gets consistently favorable reviews.
Here’s the list from Newegg, perhaps you can find these across the pond :


It took me over 4 hours just to write that post last night (including a bit of last minute research), and then decided it needed a little edit. I finished at 01:00, got to bed at 03:00 and finally got to sleep at 04:30. CDFreaks can be very addictive!

Thank you for letting me know about those Sparkle PSUs. I am going to have a good search for them in the UK because they look like they have been designed to AMD’s Athlon guidelines. I think they may be manufactured by FSP.

I e-mailed Asus (the motherboard manufacturer) and AMD last week to try and find out if the CPU if powered from the 5V or 12V rail. If I am lucky I might get an answer. If the CPU is powered from the 5V rail (or if I don’t get an answer) then I think that either one of the Sparkle PSUs or the 400W FSP would be the best option. If I bend the shelf down I should be able to get a clearance of >15mm at the end.

I could measure the actual current that my computer uses on each rail accurately by using a clamp multimeter on every pair of wires, but that would be a lot of work (and the clamp multimeter would cost as much as a PSU).


Sparkle Power Inc. appears to be North America only, but it is part of the FSP group and there are identical models on FSP’s web site. There are a number of FSP models with ideal 3.3V & 5V rails but I just can’t find anywhere selling them in the UK.


You have a Maplin’s near you? That’s where I got my 500W FSP Blue Storm II from.


[QUOTE=Ibex;2086163]Sparkle Power Inc. appears to be North America only, but it is part of the FSP group and there are identical models on FSP’s web site. There are a number of FSP models with ideal 3.3V & 5V rails but I just can’t find anywhere selling them in the UK.[/QUOTE]

Try (as Arachne has posted) Maplins.
Click on check stores stock.
You can then enter postcode to check not only stock, but nearest branch to you.
Internet abounds with UK stockists.
Just the first I tried.
Sparkle aren’t really budget though.
With PSU’s budget is a mistake anyway.


No luck with Sparkle in the UK, but here’s the FSP UK resellers list:


Good work Ibex, :bow:

Another manufacturer to consider is PC power & cooling.

Their Silencer 420W looks similar to the Corsair VX450. (spec-wise)
The Silencer 500W may too much for you but the specs may be what you are looking for: single rail design.
Output +3.3V@24A,+5V@24A,+12V@35A,-12V@0.8A,+5VSB@2.5A

Happing hunting.:slight_smile:


Another site:-


Does anyone have any experience of, or opinions on, North-Q PSUs?

I ignored them originally because I hadn’t heard of them before, but they do a 400W PSU with a specified 3.3V+5V maximum of 240W.

North-Q 400W NQ-4001EXT Super Silent

I have found a review of it but their testing method is limited.


I’ve heard of them. And I have to say, not good stuff.

The link soulsurvivor posted has some nice FSP ones.


Thanks for the warning Arachne, and everyone else for their suggestions.

Does anyone know anything about specification of the FSP Saga PSUs that Maplin & Microdirect have? I e-mailed Maplin and the said that “the PSUs in question are the PN range of supplies”. My nearest Maplin is a bit too far away for me to visit at the moment so I will try to telephone the branch and see if they can tell me what the label on the PSU says.

I suspect that they are probably the ATX-xxxPNF series (the PFC version of the ATX-xxxPN range). The 400W version is rated at 150W 3.3V+5V, but I would have to check if there will be a problem with the second 12V rail (a 1A minimum load is specified). Or I might hit the jackpot and find that they are the FSPxxx-60PN range which have 220W 3.3V+5V and 30A 5V which would be ideal. I found them on FSP’s web site last week but I can’t find anywhere in the UK selling them apart from one seller on Ebay which has the FSP350-60PN. But with my luck I don’t really want to use Ebay for this sort of purchase (especially as the seller has less than perfect feedback).

I was hoping to find a PSU that offered more than 150W 3.3V+5V though as my calculations were that 150W was only the minimum I thought I would need. It was also calculated from less than ideal data so it would be good to have a safety margin. The upper end of my calculations was a 3.3V+5V requirement of 183W.

The FSP Blue Storm II 400W and 500W models can manage 152W 3.3V+5V. I can’t see any obvious advantage in getting a 400W Blue Storm instead of a ATX-400PNF, apart from the rather nice blue paint of course (but I haven’t done a full investigation yet). Any thoughts?

Arachne - Just out of curiosity what is the +5V voltage on your 500W FSP Blue Storm II? Last year Custom PC magazine reviewed it and found that the +5V voltage was always rather low and at higher loads fell below the ATX specification.

The PC Power & Cooling Silencer 500W is only rated at 130W 3.3V+5V. Inconveniently they don’t give the full specification on their web site (not even in the specification PDF file).

Asus have replied to my question about which rail is used to power the PSU. Unfortunately the answer makes absolutely no sense, clearly something has been lost in translation. At least they have tried.

Sorry it’s another long post, I seem to be making a habit of this. :stuck_out_tongue:


Arachne - Just out of curiosity what is the +5V voltage on your 500W FSP Blue Storm II? Last year Custom PC magazine reviewed it and found that the +5V voltage was always rather low and at higher loads fell below the ATX specification.[/QUOTE]

To be honest, without removing the case on the PC it’s in (a 3.4GHz Pentium D rig), I haven’t a clue. I kept the box for awhile, but I chucked it recently :doh:

Seems to work really nicely, though. FWIW, it’s run Folding @ Home a few times (100% use of both CPU cores), and it’s been fine.


Do you have any software like Speedfan installed that can show the voltages?


Got speedfan. I’ll install it tomorrow when I next use that PC.


I recently purchased a FSP SAGA AX450-PN
Have not installed it yet.
Here’s a link to specs, etc


A big thank you for that link Jflan. There is a photo of the PSU label that give the information I need, sadly I don’t think that 16A 5V & 130W 3.3V+5V will be enough. Just as well Newegg have a photo because their specification table gives the 5V maximum as 28A, a significant error that they appear to have copied from FSP USA’s web site.

In case the models in Europe are different I have e-mailed Maplin asking again for the specification.


OK, I just opened it.
On the label…

DC Output 400W (450W Peak)
+3.3V 28.0A
+5.0V 30.0A
+12V1 18A
+12V2 18A


Thank you Jflan for opening up your computer and having a look for me. :bow: So the specification given was correct, but the photograph was of the correct PSU model (very odd). Did the label give a maximum power for the 3.3V+5V combined? (If it means having to open up your computer again then I can wait for an answer from Maplin)

I have had another reply from Asus -

“Now mostly PSU are ATX12V PSU, means it supplies 12V to CPU. Older motherboards use the 5V rail, 12 rail can also used for 5 rail, so you can also use the newer PSU on your board.”

So he is saying that the motherboard uses the 5V rail, but suggests that it can also use the 12V rail. Presumably it uses the 12V rail when it decides that the 5V rail can’t deliver enough power (when the voltage drops?).

So should I take his word that a newer PSU will be OK, or should I take the safe option and still only get a PSU with at least 150W 3.3V+5V and 25A 5V? A difficult decision as there is still a certain ambiguity in Asus’ reply. If I base my calculations on the CPU being powered from the 12V rail then the 3.3V+5V requirement drops to about 100W (with an upper estimate of 130W). This is within the specification of any of the PSUs mentioned and I would have the option of the single 12V rail Corsair VX450.

If I still go for a PSU with 150W 3.3V+5V then the choice seems to be three FSPs; a Saga model, ATX-400PNF or Blue Storm II 400W. All of these have 2x12V rails and specifiy a minumum load of 1A on each 12V rail. The ATX 2.x specification (appears to) say that the CPU power connector should be run from its own 12V rail, and FSP do say in the descriptions for several other (but similar) PSUs that the CPU has its own 12V rail. The 1A minimum load that FSP and other manufacturers specifiy does seem to be important. I found a review of a similar FSP model that measured the voltages with no load on the PSU and the 12V rails were measured at over 14V. But this was with no load on either 12V rail. I am hoping that I will get a reply from FSP about this. The only single 12V rail PSU which I have seen that can manage 150W 3.3V+5V was the one on Ebay.

So no decision just yet.