Sign in with
Sign up | Sign in
Your question

Crazy PSU fault

Last response: in Components
Share
September 18, 2012 12:53:14 PM

Hi

Here is my system

i5 2500k
8gb ddr3 in 2gb sticks think its 1033
gtx460 2gbram
500gb samsung HDD
dvd writer
wireless adaptor card

There is no overclock and the temps hover round 60deg with prime 95 running. Now comes the fun bit.

I bought an Antec HCP750 from ebay and thought it was a beast but it kept on shutting down at random times during gaming. I asked the seller if they could help and they sorted out a replacement (brand new) which apparently does exactly the same ducking thing :fou:  , not even particularly while gaming it seems. The real headduck here tho is that inbetween the first one being a bugger and failing and receiving the new i bought a second hand OCZ Modxstream 700 from a guy that was local and it runs a dream with that. Any ideas, or are Antec just pants?

Cheers for any enlightenment ppl!

More about : crazy psu fault

September 18, 2012 1:54:15 PM

Well i must say that seems to clear it up. Presumably i have a non-stable motherboard supply which is simply turning the power request off from the mobo on the 24pin maybe? Thanks for your efforts....looks like another long winded return to Antec with the request of a free upgrade to the 850 so i doesn't happen again, ;) 


delluser1 said:
There would appear to be some issue's going on with that model
http://www.jonnyguru.com/forums/showthread.php?t=9367

Are Antec just pant's ? No

Related resources
a b ) Power supply
September 18, 2012 2:05:59 PM

When hardwaresecrets reviewed the HCP750, they had to go through three samples to get one that worked as expected.

http://www.hardwaresecrets.com/article/Antec-High-Curre...

I have a hard time imagining why a DC-DC type PSU could have problems cross-regulating its 3.3V output when each voltage rail is independently regulated.
a b ) Power supply
September 18, 2012 2:56:49 PM

Antec is a pretty good company in general. Most people rate it as one of the top 4. OCZ, on the other hand, usually isn't included in anyone's top 4 list.

However, there are quite a few of Antec's model lines that are pretty sub par. Antec sub-contracts the manufacture of its PSUs to other companies (Seasonic and Delta) and Seasonic is a whole lot more respected than Delta is. The Seasonic ones generally always perform well, but the Deltas not so much.

I just looked it up and the High Current Pro models are indeed made by Delta.

That being said, Antec has this thing they do where they like to split up the power among multiple different things the industry calls "rails".

In laymans terms say you had 100 amps of power. You could put that whole 100 amps on one wire or you could split it up among 4 wires each with 25 amps. You could also theoretically split it among 20 wires each with 5 amps.

Pretend you did the 20 wire thing with 5 amps each. If you had a device that used 6 amps, you would have to find a way to connect it to two different wires, because with a cap on 5 you can't get 6 out of just one wire. Depending on the design of your thing, this could potentially be impossible and you could be forced to just forego using the 6 amp thing.

Going back to the way this all fits in, Antec likes to split their wires at least in half and often times 4 ways. The HCP 750 does indeed split it 4 ways with 40 amps on each rather than 1 rail of 160 amps. You can see this if you look on the PSU itself. It says on there:
12v1@40A
12v2@40A
12v3@40A
12v4@40A

Now, that is still a lot. 40x 12 is 480 watts of power which means one rail is still more than your whole system can possibly use. If you had a more powerful system or a less powerful Antec PSU and you put everything on one rail it could potentially give you fits.

It doesn't really apply here, but I just wanted to explain how this works to you in case it might help you in the future. In systems that have multiple different 12v lines with low amps on each one rather than just 1x 12v line with a really high number of amps on it, it can often help to re-arrange the power cables because that might move the load from one line to another and get you below the break point.

As I mentioned, though, if its true that each of those can do the whole 40a like they say they can, then that isn't your problem, because that whole system doesn't use 40A.

If so, then it does seem to be more that the particular model of PSU that you have out of their lineup just sucks. It is a Delta model so I could easily believe it.

I wouldn't say that Antec is in general a bad brand, but they can be pretty spotty. It is for that reason that I usually steer people away from Antec and more towards the Seasonic and XFX brands, both of which use Seasonic for 100% of their models. There is no spotty quality in either of these brands, every single model is good for both. In the future, you might want to think about getting one of those two brands, that way you don't accidentally end up with a lemon.

Anyway, I hope you somehow benefit from that explanation in the future and I am glad you are working with the OCZ PSU.

- Edit - The posters above pointed to HardwareSecrets and JohnnyGuru tests that say the HCP 750 sucks. These are both the two best testing websites for PSUs and if they both agree something sucks then it probably does. I would highly recommend seeing if any PSU you intend to buy has been tested by them before you buy it and avoiding the purchase if they either haven't tested it or if they gave it a bad review.
September 18, 2012 3:18:43 PM

Ain't hindsight a wonderful thing. ;)  You think Antec will acknowledge the fault and sort me out with something stable? Maybe i could ask for a seasonic one? xD

The rails thing i pretty much ignored since my system is nothing out of the ordinary but i'm certain i've not got it all working off one rail anyway cos i messed around with the first one thinking that might be the case....not to mention the fact that the OCZ has two 25W rails only. Basically i think it's either the 3 or 5 volt fluctuation that is causing it. Can't remember if it's the 3 or 5 that give the unit the power up command from the mobo....hence i was wondering however whether i could simply modify a bios setting to bypass this. Is that possible? and if so would it increase the chances of any damage being done to mobo components or anything else?
a b ) Power supply
September 18, 2012 3:26:02 PM

Raiddinn said:
Pretend you did the 20 wire thing with 5 amps each. If you had a device that used 6 amps, you would have to find a way to connect it to two different wires, because with a cap on 5 you can't get 6 out of just one wire.

If it were practical and cost-effective to current-limit on a per-wire basis, this would be the preferred method since it would make it impossible to draw enough current through a single wire to cause a wire insulation meltdown. Current limiting on a per-wire basis does not exclude power-limiting on a bulk basis and "oversubscribing" outputs in such a way that the bulk output may have 50A and have 20 individually limited wires at 5A each. This is similar to the outputs' maximum power rating VS the max combined power or how your home's power distribution panel's total breaker ratings is likely much higher than your mains breaker/fuse rating.

The Molex, ATX12V, EPS12V and PCIe connectors all have a 3-5A current limit per pin in their specification, which is why they have multiple 12V+GND pairs. If a load needs 6A, it will need a 2x2 or 2x3 auxiliary power connection and whatever current it does not need remains available on the bulk-limited output for use by any of the other wires.
a c 243 ) Power supply
September 18, 2012 3:35:04 PM

Link I provided leads to a discussion regarding the currently reviewed model
Shows a problem with it, doesn't say it sucks
Previously reviewed units of the same platform have shown that it does well, they can be found in the discussion
What it point's to is the possibilty of a bad batch
a b ) Power supply
September 18, 2012 4:08:06 PM

helpmeguys said:
Ain't hindsight a wonderful thing. ;)  You think Antec will acknowledge the fault and sort me out with something stable? Maybe i could ask for a seasonic one? xD

The rails thing i pretty much ignored since my system is nothing out of the ordinary but i'm certain i've not got it all working off one rail anyway cos i messed around with the first one thinking that might be the case....not to mention the fact that the OCZ has two 25W rails only. Basically i think it's either the 3 or 5 volt fluctuation that is causing it. Can't remember if it's the 3 or 5 that give the unit the power up command from the mobo....hence i was wondering however whether i could simply modify a bios setting to bypass this. Is that possible? and if so would it increase the chances of any damage being done to mobo components or anything else?


The same model line isn't traditionally split between OEMs. You would have to ask for them to take your HCP model and give you something that is not a HCP model instead. Since they mostly like to replace with the exact same sort the person already had, this could potentially be difficult to get them to agree to. However, if you were successful in getting them to take the Delta model and give you a Seasonic other-model from where I sit you would be better off.

Not everyone agrees with me on everything, though, so keep that in mind.

In any event, it is entirely possible for a PSU with 4x 40A lines to fail on something a PSU with 2x 25A does not fail on as long as the total amount used is 41A or more. Not that it relates to this current problem in particular, its just worth mentioning.

The +5vSB line is what is always on even when the computer is turned off. It provides power to the power button and other devices necessary to potentially waking the computer up notably including all USB devices whether they can actually wake up the PC or not.

The +5vSB line on most PSUs does tend to deteriorate more rapidly than other lines most of the time, in my experience. They all deteriorate over time, but that one tends to go the fastest. If it were an old PSU we were talking about, I would say its entirely possible that the +5vSB line deteriorated to the point it wouldn't work anymore.

However, we are experiencing problems with apparently new PSUs of given model X and its pretty uncommon for a PSU to arrive new with a failing +5vSB line.

I wouldn't guess that the +5vSB line on the HCP 750w would be the fault, but its indeed possible.

The testing websites listed before might go deeper into detail about which specific parts they had fail in the PSU themselves, but I am just guessing it is something else.

In any event, I would say its better just not to use a spotty model and not to hope to get a good one of that type rather than one of the bad ones. It is easier to just get something a different model line. I would vote for trying to talk Antec into giving you a better reviewed other-model as a replacement.
September 18, 2012 4:27:23 PM

I'm kinda with delluser on this one since the RMA would have come from the same stock as the original...most likely. I read the reviews and they seemed to say (correct me if i'm wrong) that basically on one of the units they had a drop in the 3.3v line and the other had a drop in the 5v line. This seems (the 5v at least) to fit with what i have seen since it reboots each time immediately. Any info about options in the bios for setting the voltage limits on the 5v?

I will try and get Antec to acknowledge the problem and see what they say with regards to a replacement. I can't see the point in going back to the supplier since they DO appear to just sell the faulty ones, bad press for them....maybe i should just point them to that review purely out of the goodness of my heart ;) .

Thanks to all you for putting in the effort to answer my query....if i could work out where the 'solved' button is i would hit it. Or is that for a specific type of thread?
a b ) Power supply
September 18, 2012 4:46:53 PM

You have to choose a best answer, then a moderator will mark it as solved.

I doubt you will be able to set any kind of limits on the PSU through the BIOS, it isn't really controlled there. That stuff is controlled by hardware inside the PSU itself.
!