Coolermaster Masterwatt 550 8p to 6+2p

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Hello. I have a spare Masterwatt 550 which I was given, but I want to confirm if the 8p to 6+2p pcie cable is actually the one that should be supplied with it.

Any owners of this Series of PSU that can help?
 
If you mean cable's GPU end most PSU's have that end split to 6+2 pins to fit lower graphics cards using only 6 pin connector.

But what PC parts are you trying to power with it and what's PSU's precise model number?
Some of those are pretty cheap generic PSUs.
 
Part number MPX-5501-AMAAB-UK (apparently HEC is the OEM) and powering a MSI RX580 Armor.

With some investigation and a multimeter I was able to determine that the cable I have is for a Corsair and that whilst the cable did fit into the PSU, the Ground and Live pins were essentially the opposite of what they should have been. Finding a replacement cable for that particular series of PSU isn’t easy it seems (at least I tried and failed). I’ve swapped the pins around and tested with a multimeter and all is well.

Another question that I haven’t found an answer to yet surrounds the “sense” pins and their intended purpose.
 
That's rather mediocre PSU and would plane replacing it when warranty ends if your PC has more than minimum daily usage.

As rule never try to use cables from another PSU, because of those differences in wiring.
There can be different cables even inside same brand PSUs, with many branders buying their PSUs from multiple OEMs.
And even actual own brand selling makers have occasionally changed cables.

Sense wires are for measuring voltage in cable's component/load end.
Current causes voltage loss in wiring and measurements inside PSU give higher voltage than what powered component actually gets.
 
That's rather mediocre PSU and would plane replacing it when warranty ends if your PC has more than minimum daily usage.

As rule never try to use cables from another PSU, because of those differences in wiring.
There can be different cables even inside same brand PSUs, with many branders buying their PSUs from multiple OEMs.
And even actual own brand selling makers have occasionally changed cables.

Sense wires are for measuring voltage in cable's component/load end.
Current causes voltage loss in wiring and measurements inside PSU give higher voltage than what powered component actually gets.

Whilst the modified cable works fine, I contacted Cooler Master who are sending me new cables FOC (brilliant customer service).

I'm getting rid of the rig it's in (had spare parts since I upgraded to the AM4 platform) so I'm not too concerned about replacing it as it's fit for purpose (there's also 3 years left on the warranty).

Thanks for the explanation.
 
Hey mate, could you detail how you contacted Cooler Master support? I've contacted them through CM Fanzone Support but they said the part isn't available. I'm looking for the same MasterWatt 550w PCI-e cable that you got from them.
 
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