Page 4 of 5 FirstFirst ... 2345 LastLast
Results 31 to 40 of 42

Thread: Hold-up time explained

  1. #31
    Join Date
    Oct 2006
    Location
    jonnyGURU forums, of course!
    Posts
    17,359
    Thanks Thanks Given 
    579
    Thanks Thanks Received 
    660
    Thanked in
    482 Posts

    Default

    It is kind of silly that MOST of the world uses 230V, but standards are defined in the vacuum of a 115V country.

    Surely cost savings can't be the only reason why PSUs don't come with caps that are capable of 17ms.. or even 20ms.. hold up time. There shouldn't be an effect on efficiency as well, should there?

    Has anyone here experimented with replacing a bulk cap with one of larger capacitance and tested to see what the effects are?

    I might have to do that some day.

  2. #32
    Join Date
    Jan 2010
    Location
    Greece
    Posts
    1,543
    Thanks Thanks Given 
    193
    Thanks Thanks Received 
    22
    Thanked in
    13 Posts

    Default

    longer hold-up time. I did this in a Corsair PSU Don't remember which though.. However I didn't run the whole efficiency tests. Normally efficiency should be a little lower because higher capacity needs higher amperage to charge the cap.

  3. The Following User Says Thank You to crmaris For This Useful Post:

    ehume (02-25-2017)

  4. #33
    Join Date
    Oct 2006
    Location
    jonnyGURU forums, of course!
    Posts
    17,359
    Thanks Thanks Given 
    579
    Thanks Thanks Received 
    660
    Thanked in
    482 Posts

    Default

    Yeah. That's what I was thinking. Same problem with adding caps to the secondary to reduce ripple. You also kill your efficiency.

  5. The Following User Says Thank You to Jon Gerow For This Useful Post:

    ehume (02-25-2017)

  6. #34
    Join Date
    Sep 2010
    Location
    New Jersey, USA
    Posts
    1,441
    Thanks Thanks Given 
    937
    Thanks Thanks Received 
    26
    Thanked in
    24 Posts

    Default

    In shopping for PSU's (admittedly something I won't be doing for a while) I'll gladly sacrifice some efficiency for adequate holdup time and lower ripple. I just wish manufacturers were a little more transparent in their tradeoffs for (efficiency vs. holdup time vs. ripple) vs. cost (therefore price). If the customer is seeing that a higher price gets a better PSU then he/she can make a reasoned decision.
    Core i7 4770K @4.3GHz + iGPU | GA-Z87X-UD4H | 2x8GB Crucial Ballistix DDR3@1600MHz
    Prolimatech Armageddon heatsink w/ 2 x 140mm NF-A14 PWM fans
    Samsung 840 Pro 512GB SSD | WD Red 3TB backup disk | Seagate 1 TB SSD USB file drive
    Fractal Design Define R5 case w/2 x NF-A14 ULN front fans | no exhaust fan; grill removed
    PSU Seasonic X-650 Gold

  7. #35
    Join Date
    Oct 2006
    Location
    jonnyGURU forums, of course!
    Posts
    17,359
    Thanks Thanks Given 
    579
    Thanks Thanks Received 
    660
    Thanked in
    482 Posts

    Default

    Quote Originally Posted by ehume View Post
    In shopping for PSU's (admittedly something I won't be doing for a while) I'll gladly sacrifice some efficiency for adequate holdup time and lower ripple. I just wish manufacturers were a little more transparent in their tradeoffs for (efficiency vs. holdup time vs. ripple) vs. cost (therefore price). If the customer is seeing that a higher price gets a better PSU then he/she can make a reasoned decision.
    Unfortunately, efficiency is easily quantifiable to the end user due to 80 PLUS, their independent testing and the logos they give out. Sure, reviewers will expose if a PSU has poor hold up time and/or ripple suppression. The majority of buyers don't read reviews, but do know what the 80 PLUS logo is and assumes it's a marque of quality.

  8. The Following User Says Thank You to Jon Gerow For This Useful Post:

    ehume (02-25-2017)

  9. #36
    Join Date
    Jul 2009
    Location
    Germany
    Posts
    3,715
    Thanks Thanks Given 
    6
    Thanks Thanks Received 
    74
    Thanked in
    68 Posts

    Default

    Quote Originally Posted by jonnyGURU View Post
    Has anyone here experimented with replacing a bulk cap with one of larger capacitance and tested to see what the effects are?
    Don't have the equipment for that, sadly
    But that seems to be an interesting question.

  10. #37
    Join Date
    Jun 2016
    Location
    Australia
    Posts
    166
    Thanks Thanks Given 
    327
    Thanks Thanks Received 
    0
    Thanked in
    0 Posts

    Default

    It obviously can be done, just look at the seasonic primes with their long holdup times and their high efficiency but it is just expensive

  11. #38
    Join Date
    Oct 2016
    Location
    Brazil
    Posts
    206
    Thanks Thanks Given 
    177
    Thanks Thanks Received 
    0
    Thanked in
    0 Posts

    Default

    Quote Originally Posted by jonnyGURU View Post

    Has anyone here experimented with replacing a bulk cap with one of larger capacitance and tested to see what the effects are?
    Behemot did this in his review of the Corsair CX550M. However, he also used caps with lower ESR than the original one. As the result, he got slightly less ripple and more efficiency.

    http://www.hardwareinsights.com/wp/c...esign/7/#Bonus

    On a sidenote, I personally prefer to pay more attention to inrush current.

  12. The Following User Says Thank You to Internet For This Useful Post:

    Jon Gerow (02-26-2017)

  13. #39
    Join Date
    Oct 2006
    Location
    jonnyGURU forums, of course!
    Posts
    17,359
    Thanks Thanks Given 
    579
    Thanks Thanks Received 
    660
    Thanked in
    482 Posts

    Default

    Quote Originally Posted by Internet View Post
    Behemot did this in his review of the Corsair CX550M. However, he also used caps with lower ESR than the original one. Seems this also was responsible for slightly less ripple and more efficiency.

    http://www.hardwareinsights.com/wp/c...esign/7/#Bonus
    I see that now.

    Also, our engineers told me that cost of the cap is about the only gating factor.

  14. The Following User Says Thank You to Jon Gerow For This Useful Post:

    ehume (02-26-2017)

  15. #40
    Join Date
    Jan 2010
    Location
    Greece
    Posts
    1,543
    Thanks Thanks Given 
    193
    Thanks Thanks Received 
    22
    Thanked in
    13 Posts

    Default

    using caps with lower ESR won't necessarily do good. In some cases it might also bring worse results because even ESR plays a role in a PSU by helping in preventing unwanted oscillations. I am referring to the secondary side's filtering caps.

Similar Threads

  1. Jonny reviews lack the Hold Up Time test.
    By sblantipodi in forum Testing Methodology Discussion
    Replies: 91
    Last Post: 10-01-2020, 10:31 AM
  2. What to do with such screwed hold-up time?
    By Behemot in forum PC Power Supply Discussion
    Replies: 5
    Last Post: 02-12-2017, 12:04 AM
  3. Exploding hold-up time measurement
    By crmaris in forum PC Power Supply Discussion
    Replies: 7
    Last Post: 04-24-2016, 03:47 PM
  4. Sirfa's Hold-up time tricks
    By crmaris in forum PC Power Supply Discussion
    Replies: 33
    Last Post: 03-07-2016, 02:50 PM
  5. Auto-Tune Explained
    By Oklahoma Wolf in forum Off Topic
    Replies: 3
    Last Post: 11-26-2009, 01:46 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •