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The Power supply Problem

NutJob3869
By NutJob3869
in Power Supplies
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I am currently thinking of upgrading to a Intel I5 2500k, ASUS P8Z68-V and Artic Cooler which has been professionally overclocked. (I found the bundle on ebay) and  realised that my power supply only has a 4-pin Cpu power connection whereas this motherboard has an 8-pin power connection. I have looked online and there are adapters available which will port the 4-pin plus a molex cable to an 8-pin. Is this a good idea for a gamer on a strict budget?

EDIT: I don't know if this is important but I plan to plug in a sound card and gtx 1050ti

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3 minutes ago, emosun said:

If your power supply doesn't have an 8pin cpu connector it's probably a pretty crappy power supply. What the make and model of the power supply?

It's a second hand ACE 550w A-550BR. Reposting because I forgot to quote you

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42 minutes ago, NutJob3869 said:

If I was to try and run my setup with this power supply and it ends up drawing more power than the supply can handle. Would I damage any components in the process? 

No, it will just shutdown.

^^^^ That's my post ^^^^
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The 8 pin connector is to provide more total power to your processor, if the processor needs it.

A single pair of wires is designed to carry up to 7A (if it's an 8 pin connector) or 9A of current (for the 4 pin connector) to the DC-DC converter that feeds power to the processor, so a 4 pin connector will in theory be able to give the DC-DC converter up to 2 pairs x 9A x 12v = ~ 220 watts.

If you had an 8 pin connector, the maximum allowed current the DC-DC converter is supposed to take from the power supply would be 4 pairs x 7A x 12v = ~ 335 watts.

 

Your i5-2500k has a TDP of 95w, so without overclocking it shouldn't use more than around 85-100 watts when abused with various benchmarks. When overclocked slightly, the processor will probably go up to maybe 150 watts... note that all these numbers are all below the maximum of 220 watts that's allowed through a 4pin connector, so upgrading to an 8 pin cable won't really make much of a difference.

 

You would do it only if you're really trying to overclock to the max and you want safer and better power delivery to the processor by having more wires in that connector. With 4 pairs of wires, the connector and the wires themselves will heat less when there's a lot of current going into the motherboard.

 

Note though that a different connector won't make the power supply suddenly capable of delivering more power to the motherboard.

A cheap power supply that has only a 4 pin connector probably can only output a small amount of current on 12v, from where the CPU, pci-e slots, graphics cards and fans take most of their power.

 

If the system works fine now, don't mess with it, it won't make the system faster or better.

 

later edit:  According to https://www.box.co.uk/550W-Ace-Value-Black-PSU-24Pin-with-12cm_1084262.html

550W Ace Value Black PSU 24Pin with 12cm Fan SATA Power Supply,121 Year Warranty
 
Your power supply should be able to provide (14A + 14A ) x 12v = 336 watts of energy on 12v.
 
Without overclocking, your processor will use up to 100 watts, the motherboard will use maybe 5-10 watts, each fan will use around 2-3 watts, mechanical hard drives will use up to around 5-10 watts.
So in theory, if the power supply is honest and doesn't lie about its capability, you would still have about 200 watts of energy available to use for various things.
 
A GTX 1050ti will use up to 75 watts, which means it will need a pci-e 6pin because according to the PCI-E standards, it's only allowed to take up to 60-65 watts from the pci-e slot (the power for these come from the 24pin connector).

So the video card will probably take around 30-40 watts from the slot, and around 30-40 watts from the other connector, and because of this it should be fairly safe to use a simple MOLEX or SATA to pci-e 6pin adapter to power such a video card.

 

However, normally, when I see a power supply with just a 4 pin CPU power connector and no PCI-E connectors, I suspect that the power supply may have much lower power output in reality.

You can already see that while the psu is advertised as 550w, in reality it can only output 336w on 12v which is what's used most often in modern computers.. but I have a strong suspicion the psu may not even be able of 336 watts.

I would be comfortable saying the power supply can definitely do at least 250 watts, which would still be enough to power your system with that GTX 1050ti video card, if you'll not overclock the processor.

 

But... you should definitely consider and save money to buy a better quality power supply from a known brand name, even if it's some of their lower end 450-550w models.

 

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1 hour ago, mariushm said:

The 8 pin connector is to provide more total power to your processor, if the processor needs it.

A single pair of wires is designed to carry up to 7A (if it's an 8 pin connector) or 9A of current (for the 4 pin connector) to the DC-DC converter that feeds power to the processor, so a 4 pin connector will in theory be able to give the DC-DC converter up to 2 pairs x 9A x 12v = ~ 220 watts.

If you had an 8 pin connector, the maximum allowed current the DC-DC converter is supposed to take from the power supply would be 4 pairs x 7A x 12v = ~ 335 watts.

 

Your i5-2500k has a TDP of 95w, so without overclocking it shouldn't use more than around 85-100 watts when abused with various benchmarks. When overclocked slightly, the processor will probably go up to maybe 150 watts... note that all these numbers are all below the maximum of 220 watts that's allowed through a 4pin connector, so upgrading to an 8 pin cable won't really make much of a difference.

 

You would do it only if you're really trying to overclock to the max and you want safer and better power delivery to the processor by having more wires in that connector. With 4 pairs of wires, the connector and the wires themselves will heat less when there's a lot of current going into the motherboard.

 

Note though that a different connector won't make the power supply suddenly capable of delivering more power to the motherboard.

A cheap power supply that has only a 4 pin connector probably can only output a small amount of current on 12v, from where the CPU, pci-e slots, graphics cards and fans take most of their power.

 

If the system works fine now, don't mess with it, it won't make the system faster or better.

 

later edit:  According to https://www.box.co.uk/550W-Ace-Value-Black-PSU-24Pin-with-12cm_1084262.html

550W Ace Value Black PSU 24Pin with 12cm Fan SATA Power Supply,121 Year Warranty
 
Your power supply should be able to provide (14A + 14A ) x 12v = 336 watts of energy on 12v.
 
Without overclocking, your processor will use up to 100 watts, the motherboard will use maybe 5-10 watts, each fan will use around 2-3 watts, mechanical hard drives will use up to around 5-10 watts.
So in theory, if the power supply is honest and doesn't lie about its capability, you would still have about 200 watts of energy available to use for various things.
 
A GTX 1050ti will use up to 75 watts, which means it will need a pci-e 6pin because according to the PCI-E standards, it's only allowed to take up to 60-65 watts from the pci-e slot (the power for these come from the 24pin connector).

So the video card will probably take around 30-40 watts from the slot, and around 30-40 watts from the other connector, and because of this it should be fairly safe to use a simple MOLEX or SATA to pci-e 6pin adapter to power such a video card.

 

However, normally, when I see a power supply with just a 4 pin CPU power connector and no PCI-E connectors, I suspect that the power supply may have much lower power output in reality.

You can already see that while the psu is advertised as 550w, in reality it can only output 336w on 12v which is what's used most often in modern computers.. but I have a strong suspicion the psu may not even be able of 336 watts.

I would be comfortable saying the power supply can definitely do at least 250 watts, which would still be enough to power your system with that GTX 1050ti video card, if you'll not overclock the processor.

 

But... you should definitely consider and save money to buy a better quality power supply from a known brand name, even if it's some of their lower end 450-550w models.

 

Thanks very much for your insight. But I would like to correct you on a couple of areas. I trust my power supply to a certain extent because I have been using it in this PC for the last 3 years and it has never skipped a beat, though I asked this question to see if it might start to be overwhelmed with a PC that isn't a potato. I am also planning to buy a 1050 ti that does not sport a 6-pin pci-E port. I haven't bought all of this stuff yet, it is an ad on eBay and it claims to be professionally overclocked buy a place in Bolton so I would prefer to keep that overclock as I couldn't do it properly myself if I took off the overclock and tried to put it back on. I will probably try to limp it for a bit until I have money to get something reputable with an 80 plus bronze rating.

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Sure, there's lots of versions of video cards, i merely said that the best GTX 1050 TI out there will use up to 75w, which will require having a separate pci-e connector, because it's more than the allowed 60-66 watts (some specifications say maximum 5A from 12v, therefore 60w ... others say the proper value is 5.5A at 12v, which would be 66w)

The cards can also take as much as 10 watts from 3.3v available in the pci-e slot, though few do.

 

Some models may have only have 2 GB of memory instead of 4 GB, which will reduce the power consumption a bit, so they'll fit within those 60-66 watts of power consumption. Or, they'll configure the default frequencies for the GPU chip or for the memory lower than normal, which will also reduce the maximum power consumption.

 

So some graphic cards will be made without additional power connectors but that power will still come from the slot, or more exactly from the only two pairs of 12v wires in the 24 pin connector. Instead of getting power from 3 pairs of wires in the 6 pin connector, your graphics card will get power from only two pairs of wires which are also further away, making the power quality worse.

 

Really, you'd be better off buying a video card WITH an additional power connector, will be overall better video card, with better performance for the money.

 

 

 

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