No 8 pin PSU cable to power up the CPU 8 pin connector on motherboard
Hello. I have a motherboard MSI B250m PRO-VDH and it have an 8 pin connector to power up the CPU i3-7100 , there problem is that my psu doesn't have 8 pin cable but only 6 and 4 pin (6 pin comes together with another 2 pin cable but it doesn't fit the connector on the motherboard), So I was wondering whether I can use 4 or 6 pin cables safely and which one is better to use.
Thanks in advance!
Thanks in advance!
Nope, don't use those, different voltage and power for those 4pin and 6pin. Mostly only use one of them will underpower the CPU. What is your PSU model? Check voltage and power for two 4-pin cables, if they are in line with MB specification, you may use those two 4-pin cables to replace 8-pin. Otherwise, better get a new PSU.
PCPartPicker part list / Price breakdown by merchant
Power Supply: SeaSonic - 520W 80+ Bronze Certified Fully-Modular ATX Power Supply ($35.89 @ Newegg)
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Generated by PCPartPicker 2017-09-25 10:05 EDT-0400
If electrical connectors in a computer don't fit, that's by design. They are keyed so that you can't plug them in incorrectly, so don't force them.
If you read the motherboard manual, it may indicate whether the CPU can be run with a single 4-pin power feed, or if it requires the 8-pin be fully populated to work correctly. On some motherboards, under certain loading conditions, this is optional, but read your manual to know.
The easier option however is to take the previous two posters' advice and just replace the power supply. A power supply at this point in time that only provides a 4-pin CPU power feed is likely to be of poor design quality, or very old.
Another option is an adapter, but most folks don't recommend them as, connectors are usually omitted from power supplies because the power supply is cheap, and the manufacturer doesn't want you to exceed it's limits.
The 4-pin ATX12V connector (2x2) should fit in one half of the EPS12 connector on the motherboard and would be sufficient in most cases. However, PSUs old enough to only support the ATX12V spec are unlikely to work well with modern CPUs' power-saving states and the fast transients they generate.