Need a new PSU 4 my CF 4870's but which one?

fornowagain · 6 Jul 2008 at 16:31

Fire Wizard said:
I'm afraid it dosen't. The +12Volt rail can only provide up to 425 watts of power which is around 36 amps. You do not simply add all of the +12Volt rails up to come to the conclusion of how many amps a power supply can provide because you cannot load up all 4 rails to their maximum simultaneously.

That's true, although the actual 12v combined wattage might be a bit more than 425W (580-155) depending on the 3.3v & 5V rail loads. From system estimates (based on mains values after efficiency losses) seen in reviews that would seem to be enough or possibly borderline depending the rest of the system. It may be the case that the psu individual rails are exceeding the OCP limits. I'd try crossloading the rails before giving up on it.

marscay · 6 Jul 2008 at 16:38

Fire Wizard said:
I'm afraid it dosen't. The +12Volt rail can only provide up to 425 watts of power which is around 36 amps. You do not simply add all of the +12Volt rails up to come to the conclusion of how many amps a power supply can provide because you cannot load up all 4 rails to their maximum simultaneously.

yeh you're right about that, but isn't it good for ~470w @ 12v assuming 80% efficiency @ 580w max peak.

Tom|Nbk · 6 Jul 2008 at 17:02

Big.Wayne said:
Enough Tom, you made your point, I made my point, job done, lets move on shall we?

Enough of what?

Me making good points which you can't counteract with a decent argument for Modular PSU's.

Right oh

fornowagain · 6 Jul 2008 at 17:19

marscay said:
yeh you're right about that, but isn't it good for ~470w @ 12v assuming 80% efficiency @ 580w max peak.

You've got that the wrong way round. It shows 580w for 12v+3.3v+5v combined. 12V could be as low as 425W if the two remaining rails were maxed. In reality it would be around the 500w mark. This is the combined 12v wattage available to the components. 580w from the rails combined after efficiency losses of say 80% would draw approx 725W from the mains.

toucam · 6 Jul 2008 at 17:21

Tom|Nbk said:
Whats your system setup.

This chart shows that the PSU only gets noisy above 500w and even then it's hardly loud

I did look at that chart and all the reviews out there before buying the PSU but it was way below my expectation in terms of noise and heat. A few people also have had the exact same problems on Corsair's PSU forum. I didn't want to risk RMAing it and had another one with the same problems. You probably have a "quieter" one because the noise it made was very apparent and coulnd't be ignored!
I buy PSU based on how it performs first and foremost and can't care less whether it's modular or not. Here's my PCPC in my case and it's okay for me with good airflow, the unused cables as you can see are tucked away not too neatly but it does the job.

Tom|Nbk · 6 Jul 2008 at 17:26

Sounds like you had a dodgy PSU then Toucam

Big.Wayne · 6 Jul 2008 at 18:06

Tom|Nbk said:
Me making good points which you can't counteract with a decent argument for Modular PSU's

I think a picture paints a thousand words Tom. . .

Your system is a real mess and your using a very old fashioned chassis, when you decided to join us in the year 2008 you may well understand why I praising the merits of a modular PSU!

It helps keep a chassis clutter free and running cool, obviously not important to you!

Big.Wayne · 6 Jul 2008 at 18:16

toucam said:
I buy PSU based on how it performs first and foremost and can't care less whether it's modular or not. Here's my PCPC in my case and it's okay for me with good airflow, the unused cables as you can see are tucked away not too neatly but it does the job

Hey toucam, that's my old chassis, a classic from 20003, used that model for four years or so, but compared to a modern case its really aweful.

It's one saving grace however is cavernous amounts of space so hiding cables is particularly easy. I can tell you though that chassis will make your PSU run a lot hotter due to its old fashion placment at the top, this will make the fans run louder and almost certainly decrease the units lifespan.

Now I understand why some people are still using captive cable PSU's, when you got an aircraft hanger for a chassis it matters not!

Born_2_Kill_83 · 6 Jul 2008 at 18:30

This is going from bad to worse for me!!!

Heres the lastest:
Orginally my system was cutting out underload, I unplugged 2 hard-drives, 1 DVD Writer, 1 Floppy, 3 big fans. This seem to solve the problem.

Today it got worse, power would be cut from my computer soon as I loaded any benchmark or game.(everything still unplugged)

I took out both GPUS and tested one by one with the orginal set-up, they both worked fine, including underload.

Ive put them both back in now and crossfire wont enable at all, I go to device manage and the 2nd card has the following fault:

Windows has stopped this device because it has reported problems. (Code 43)

I've tired swapping the card around again and the same fault, also the fan is on 100% on the 2nd card all the time.

HELP!!!!! :mad:

VTR · 6 Jul 2008 at 18:32

Sounds like the PSU is dieing and is getting worse by the day to me.

easyrider · 6 Jul 2008 at 18:33

My 620w Enermax liberty ok?

Tom|Nbk · 6 Jul 2008 at 19:00

Big.Wayne said:
Your system is a real mess and your using a very old fashioned chassis, when you decided to join us in the year 2008 you may well understand why I praising the merits of a modular PSU!

A real mess to who? you?

I don't give a flying **** what you think in all honesty Wayne, since when did you become the expert in any case?. Perhaps if you spent less on extravagant "thermally enhanced" cases you may have more cash for some real hardware.

I buy things that get the job done.

There are no viable benefits of a modular PSU to an enthusiast who has a lot of kit to power and no doubt would end up using most of the cables anyway, I made this point but you bumbled and couldn't come up with a viable argument for them apart from the fact you now suddenly have better cable management somehow :confused:

Oh I'm sorry I didn't realise TWO less cables in my case would make THAT much difference. How wrong I am.

Big.Wayne said:
It helps keep a chassis clutter free

Clutter free? what am I living in my case now or something? Who cares?! it sits in my workstation and does it's thing for all I could care there could be a thousand midgets having a party in there it wouldn't bother me aslong as it still does it's job which is to house all my hardware comfortably.

Big.Wayne said:
and running cool, obviously not important to you!

PC runs pretty cool to me I'm sorry when was the last time you checked out my idle and load temperatures. I didn't notice you stood over my shoulder when I was benching.

Big.Wayne · 6 Jul 2008 at 19:02

VTR said:
Sounds like the PSU is dieing and is getting worse by the day to me.

From the evidence presented that would be the most likely thing.

Test the PSU with a PSU tester . . .

fornowagain · 6 Jul 2008 at 19:03

Big.Wayne said:
I think a picture paints a thousand words Tom. . .

Your system is a real mess and your using a very old fashioned chassis, when you decided to join us in the year 2008 you may well understand why I praising the merits of a modular PSU!

It helps keep a chassis clutter free and running cool, obviously not important to you!

Baiting and unwarranted. RTMed.

Big.Wayne · 6 Jul 2008 at 19:06

Sorry fornowagain? what does that mean?

[edit] baited lol, did u read this post?

Tom|Nbk · 6 Jul 2008 at 19:14

3. DON'T LOSE POWER WITH MODULAR PLUGS

Due to their look, convenience, and cost savings for manufacturers, modular plugs have become a popular power supply feature. Unfortunately, there has been little or no discussion of the impact of this feature on overall performance and reliability. The fact is, modular plugs limit power by adding to electrical resistance. The voltage drop can be as much as would occur in 2 feet of standard wire. Worse yet, modular plugs utilize delicate pins that can easily loosen, corrode, and burn, creating the potential for a major system failure. That's why professional system builders specify uninterrupted wire!

Shock horror as one of biggest PSU manufacturer doesn't make Modular supplies.

http://www.pcpower.com/technology/myths/#m4

And I thank you and Good night!

Big.Wayne · 6 Jul 2008 at 19:17

Grow up Tom!

gareth170 · 6 Jul 2008 at 19:19

having a lot of cables can't be helped. it depends on how many hardware they have in they case, if a person as 6hdd's, 3dvd drives, front panel controllers, and whatever else of course there will be more cables than if a person had 1hdd, 1dvd drive..

also in a big case, having a lot of cables it doesn't make heat issue much.

Tom|Nbk · 6 Jul 2008 at 19:21

Big.Wayne said:
Grow up Tom!

More attacks because someone can't conclude a viable arguement. Yay

gareth170 said:
having a lot of cables can't be helped. it depends on how many hardware they have in they case, if a person as 6hdd's, 3dvd drives, front panel controllers, and whatever else of course there will be more cables than if a person had 1hdd, 1dvd drive..

Yep if you have a lot of hardware. How the hell is a modular PSU going to help in anyway since you're going to have to use all the cables anyway!

It completely defeats the object but some can't see

Big.Wayne · 6 Jul 2008 at 19:26

gareth170 said:
it depends on how many hardware they have in they case

This is true, funny how we assume everyone and their Dog has the same amount of computer kit as ourselves?.

gareth170 said:
there will be more cables than if a person had 1hdd, 1dvd drive..

That's me and most people I know in real-life

I have two SATA hard-disks, one SATA Optical and a graphics card which need one 6-pin PCI-e.

Obviously I need hardly any cables, hence why I am saying modular PSU's are the business.

Maybe it is the fact that I have builts dozens of systems for clients and friends, I may think differently if I built one PC every two/three years.

The worst part of a PC build for me personally is integrating PSU. cables neatly.