Power Supply Unit (PSU) FAQ

[That_Guy]

I have an Apevia / Iceberg / 680-Watt PSU with 2x6pin PCI-E connectors and now i've got GeForce 9800 GX2 using 1x6pin AND 1x8pin PCI-E connectors. Question is: are there 6-to-8 PCI-E adapters and if there are such, is it SAFE to use one in my case?

 

 

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Update: Well after a short research i have answered the first part of my own question: Yes, the adapters/converter do exsist. Even that some people do use them to power up their cards. But as to the second part of it, it is still unclear to me how safe is it to do so. According to what i found 6pin connectors provide 75 W @ 107 peak power while 8pin provides 150W. I am not a pro at that stuff so could someone explain me what can happen or what damage can occur if i use an adapter/converter. Thanks.

 

 

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Well just got that 6-to8 pin converter and it works perfectly. Question is closed

Edited September 13, 2008 by Neebitemnemo

[damian]

Q. Is a power supply with multiple 12V rails better then a power supply with one single 12V rail?

 

A. Not exactly. If the unit provides decent amperage on the 12V rail it will be sufficient, I'd say about 25A is a good contender. The reason it's best to find a power supply with a large number of amps on the 12V rails is because you do not want a certain part of a computer exceeding the power withdraw limit of the 12V rail.

 

Now this is not to say that a power supply with multiple 12V rails performs better or is far more stable then a power supply with just one large 12V rail. See in theory a unit with multiple rails is basically the same as a unit with just one large rail since the unit with multiple rails is gaining all those amp's from a certain power source. The output. They are just split 12V rails, and are split for safety precautions.

 

So a power supply with one large 12V rail and a large number of amps will be delivering the output through a single rail, instead of a unit with multiple rails sharing the current.

 

Another thing i might add, don't "look" for a power supply with multiple 12Vrails or one large 12V rail, just search around for a power supply that provides enough amps through the 12V rail/s.

[wiewior1984]

I'd like to share some of my experience:

 

Q: What do I risk by using cheap PSUs?

 

A: Basically the PC. At worst (I'm a IT Consulatant and I've seen much) The Mobo + RAM + CPU + HDD. I've seen many PCs burned to the case by CODEGEN PSU as well as Tracer PSU. However there are more cunning beasts than that. For example IBox or ModeCOM PSUs. It's common knowledge that a Codegen or Tracer fits perfectly only for long distance throwing practice. The IBox or Modecom can perform quite good at times. But they have this nasty habit of going out all out sudden when they get a little too much heat (and I really mean little). Seriously; it's safe to use a ModeCOM when You clean It VERY regulary and I mean it

 

 

Q: Are cheap PSUs completely useless?

 

A: No, You can salvage some capacitors, trafos, fans and wires for Your home DIY hobby. It is sometimes good to put a 400W tracer to a very low power consuming PC. Like a router that has an old Mobo + CPU 1xHDD and is used to serve minor services like dedicated games for Your household. They are performing quite well when You clean them every now and then.

 

 

Q: Are all cheap PSUs the same?

 

A: No, some, like ModeCom would rather burn themselves than harm the PC's components. Whereas a CODEGEN usually takes the whole PC under.

 

 

Q: Are Zalman's PSUs good?

 

A:Well, basing on my expeerience Yes and No. Yes if it isn't really a gaming rig (their Amp ratings aren't that marvelous but still are impresive) No, because Zalman did the best cooling for years and no PSU whatsoever. In My opinion (and experience) They lack (with all the respect) the experience to do a good PSU. In Poland a 550W Zalman's PSU would cost about 400PLN (about 110USD) and a Modular 600W Tagan nearly 430PLN(120USD) The Tagan went overall much better with keeping the voltage of 2xHD4850 in XFire. Tagan was just more stable with surprisingly few (and minor) peaks on 12V rail. Again, please remember that I am just describing my experience.

Edited December 22, 2008 by wiewior1984

[gustie]

Useful link http://www.pcpower.com/technology/myths

 

 

good link - thanks

[tazwegion]

Q: Are cheap PSUs completely useless?

 

A: No, You can salvage some capacitors, trafos, fans and wires for Your home DIY hobby. It is sometimes good to put a 400W tracer to a very low power consuming PC. Like a router that has an old Mobo + CPU 1xHDD and is used to serve minor services like dedicated games for Your household. They are performing quite well when You clean them every now and then.

 

 

IMHO there are no capacitors worth salvaging in low end cheapo PSUs, almost always you'll find their filtering stage components have vented (or are ready to), however providing other components are of a reasonable standard a cheap PSU can be transformed into something rather useful with a quality capacitor upgrade

Edited March 27, 2009 by tazwegion

[paulktreg]

IMHO there are no capacitors worth salvaging in low end cheapo PSUs, almost always you'll find their filtering stage components have vented (or are ready to), however providing other components are of a reasonable standard a cheap PSU can be transformed into something rather useful with a quality capacitor upgrade

 

Be careful when "upgrading" cheap power supplies. They quite often omit some filter stages, do not have power factor correction and awful efficiency, all to save costs, which no amount of new quality capacitors will rectify.

 

Cheers

 

Paul

[tazwegion]

Be careful when "upgrading" cheap power supplies. They quite often omit some filter stages, do not have power factor correction and awful efficiency, all to save costs, which no amount of new quality capacitors will rectify.

 

I said cheap NOT nasty!

 

 

I got both my pre-loved (and cap venting) Antec's for a song, however 'off the shelf' (retail) cheap are just cheap AND nasty, additionally I believe I also used the "providing other components are of a reasonable standard" qualifier to my recapping suggestion... FSP (Sparkle) PSUs aren't terribly expensive new either and make excellent candidates for a capacitor retrofit

Edited April 21, 2009 by tazwegion