PSU ripple - serious?

DennisMenace

DennisMenace

DennisMenace

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I have been considering the Coolermaster Silent Pro Gold 600W/700W for 4 reasons:
1) 80+ Gold (90% efficiency) - as it could be on almost 24/7
2) Modular - not a major issue, but tidy
3) 5 year warranty - not as good as 7, but better than 3
4) £70/£90 for 600W/700W - the cheapest 80+ Gold PSUs out there?

The main drawback I can see from checking a few reviews is the peak-peak (AC?) ripple, nearly 50mV on all rails. This is just within ATX spec for 3.3/5V, and under the 120mV limit for 12V, but still considered high for an "enthusiast" PSU.

Is this really a serious consideration? Isn't this what mobo VRMs are there for, to smooth out this ripple? Could the high ripple degrade the VRMs over time, leading to instability or failure?

Otherwise I would consider this PSU perfect (for me) - the next step up (Corsair AX?) is nearly double the price, and although I'm prepared to pay extra for a good PSU with 80+ Gold (as it should pay for itself over time), I am on a budget.

Any explanation of the importance of ripple, or suggestions for similarly priced PSUs, would be much appreciated, as I need to sort it out soon (Z68 awaits!). Thanks in advance.
 
Short answer: it's fine, it's within spec.

Long answer: You're right, regulators elsewhere will condition the voltage being supplied, but they need a limit to what inputs they are expected to handle, hence the ATX spec. The only thing to take from the fact the PSU has a higher ripplie is that the design or component selection is likely to have been done more cheaply, but having said that, since it is still within spec that *may* not be an issue. It *may* indicate cheaper components that are more likely to fail over time, but that is purely guesswork on my part.
 
Thanks for the quick answer(s).

I've just spotted the 700W on offer for £72 (inc VAT, and I get free delivery) which is proving very hard to resist, so unless someone posts in the next couple of hours to say "Don't buy it! It's terrible! Ripple is a serious flaw!", it looks like I've got the heart of my new build.

NB. Post 250 = Free Delivery with OcUK! w00t :D
 
DennisMenace said:
Thanks for the quick answer(s).

I've just spotted the 700W on offer for £72 (inc VAT, and I get free delivery) which is proving very hard to resist, so unless someone posts in the next couple of hours to say "Don't buy it! It's terrible! Ripple is a serious flaw!", it looks like I've got the heart of my new build.

NB. Post 250 = Free Delivery with OcUK! w00t :D
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I would have thought for the price you can get better quality PSUs, do you really need 700w?
 
pv123 said:
I would have thought for the price you can get better quality PSUs, do you really need 700w?
Click to expand...

Show me a better quality 80+ Gold modular PSU and I'll probably buy it.

I don't really need 700W, but it gives me the option to SLI/Xfire later. The 600W is on offer too, but only £5 cheaper.

NB. Maybe I should have mentioned this - I already have the case which has exhaust fans in the roof panel. This limits the PSU size to 150x86x160 (150 would be better, but modular/high efficiency PSUs tend to be bigger).
 
Sorry, I meant to say:
Show me a better quality 80+ Gold modular PSU for the same price and I'll probably buy it.

The cheapest I can find the FSP is ~£110 with delivery, which is well over budget. :(
Also, that review shows the FSP has a larger ripple (69/75mV) on the +12V rails than the CM-SPGold (<50mV). How significant this is, I have no idea - hence this thread.

Stulid, I'm not questioning your suggestion - any are appreciated - I know you are an all-round guru here, and I am an intellectual pygmy as far as PSUs are concerned (and in many other areas). I'm unsure as to the relative importance of various features - ripple, active PFC, regulation, Jap caps (?) etc - although I understand efficiency :rolleyes:. I just saw "80+ Gold", "Pro" and "£72" and thought it looked a bargain - until I saw the reviews mention "ripple". And I realise high-spec doesn't mean high-quality.

So could you recommend anything better, ideally:
Under ~£75(ish)
Under 160mm length (thanks to my "quirky" Godspeed case)
Ideally 80+ Gold
Ideally modular
At least 550-600W
 
 
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I know 80+ Gold narrows it down a lot, but I was just thinking of the polar bears (and my electricity bill) so that the extra investment would eventually pay for itself.

I like the look of the XFXs (and they're Seasonic), I just wish they did a 600W version closer to my budget - 750W is the smallest I can find. :(

I was originally considering the BeQuiet PurePower L7 530W @ £43, but everyone advises not to skimp on the PSU - so I upped my budget, hoping the extra efficiency would be a good trade-off. Now I'm looking at £90-£100 PSUs, which seems OTT for a £500-ish system (I'm aiming for Z68(UD3H?)/2500K with a single GPU, maybe 6950>70 or 480 SE/SOC).

I did have it narrowed down to 2 or 3 PSUs, now stulid has doubled my options. :mad: My brain hurts. :confused:

PS. Is the Silent Pro Gold really that bad? I've got about an hour to decide, or postpone and make an informed decision (hopefully).
 
Makhaira said:
The only thing to take from the fact the PSU has a higher ripplie is that the design or component selection is likely to have been done more cheaply
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Exactly, Coolermaster branded PSUs are capacitor lottery: What capacitors they got for cheap enough.
And cheap capacitors aren't good for long term reliability, even if PSU doesn't end up blowing itself up failing of capacitors starts to increase ripple which can fast put stress to VRMs (and components without own regualation) when ripple is highish to start with.

And FSP/Fortron is major maker using cheap capacitors as their trademark, and often their PSUs have mediocre ripple as factory fresh.


DennisMenace said:
I like the look of the XFXs (and they're Seasonic), I just wish they did a 600W version closer to my budget
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Quality components cost always and besides parts there are other factors so little less powered variant might not even be much any cheaper to manufacture.
 
OK guys, you managed to talk me out of it. Thanks for the advice and suggestions.

Back to the drawing board...

I see that that the PC Power and Cooling Silencer 760W is on offer (£85) this week - it's more power than I need, non-modular and over-budget, but those are minor problems (otherwise it looks pretty awesome). The bigger problem is its size - 180mm - so I'll have to disassemble my case and see if it's possible to move the exhaust fans in the roof forward (or just remove them). Or just use something the right size...
 
stulid said:
You see post #8? they are still the best options in this thread.
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Agreed, they're at the top of my list - I just checked the "This Week Only" and thought the Silencer might be another option (size permitting).

My shortlist so far (XFX Black, Corsair TX V2, PCP&C Silencer) are all Seasonics, but the Silencer has a 7 year warranty - so must be better. :rolleyes:

And then there's the NZXT Hale90, a SuperFlower (?), which is also 180mm. :(
I'll have to check the bodgability of my case first.
 
stulid said:
Does it really need to be Gold rated?

http://www.overclockers.co.uk/showproduct.php?prodid=CA-011-CS&groupid=701&catid=123&subcat=1084

Review - http://www.hardwaresecrets.com/article/505
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How can you recommend the OLD Corsair 750TX? I don't understand this. Yes it is a good PSU, but it's time has passed.

Anyway, there is a 650W version of the XFX:
http://www.overclockers.co.uk/showproduct.php?prodid=CA-002-XF&groupid=701&catid=123&subcat=
Which is 170mm long, modular, unfortunately only 80Plus Bronze.

The Corsair HX 650W apparently achieves 80Plus Silver efficiency even if Corsair don't list it as such. Don't know how long it is.

Enhance do make some good units like the Silverstone Strider Plus units they make (750W and above, maybe even the 600W version, but I haven't read a review of that one yet) and the Strider Gold units.
 
It's not a bad psu, the one I had did get a little noisey when warmed up, ended up putting a extra hole in my case to allow fresh air in.
 
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