pc not turning on when cpu 4 bin cable is plugged

makuke12 · Feb 25, 2022

So i have this problem when 4 bin cpu cable is connected pc doesn't turn on but when it isn't it turns on. Can someone tell me what can cause this? I think its psu but im not sure.

Deleted member 24505 · Feb 25, 2022

Can you list your specs, or fill it in on here https://www.techpowerup.com/forums/account/specs make sure it says yes at the top

makuke12 · Feb 25, 2022

Tigger said:
Tigger said:

Tigger said:

Can you list your specs, or fill it in on here https://www.techpowerup.com/forums/account/specs make sure it says yes at the top

Click to expand...

Click to expand...

I filled those what i knew

JrRacinFan · Feb 25, 2022

That is going to be a short in the motherboards mosfets. It;s triggering the power supplies short circuit protection to prevent damage.

makuke12 · Feb 25, 2022

JrRacinFan said:
That is going to be a short in the motherboards mosfets. It;s triggering the power supplies short circuit protection to prevent damage.

Can i fix it?

Or do anything about it?

JrRacinFan said:
That is going to be a short in the motherboards mosfets. It;s triggering the power supplies short circuit protection to prevent damage.

also my motherboard is GIgabyte GA-965P-DS3

JrRacinFan · Feb 25, 2022

makuke12 said:
Or do anything about it?

New motherboard or a PC repair shop that has the ability to do voltage injection to locate/replace the MOSFETs causing the short. The only sure fire way to correct it. Is the PSU modular? If so when you disconnect the eps 4 pin, do you also disconnect it from the PSU?

makuke12 · Feb 25, 2022

JrRacinFan said:
New motherboard or a PC repair shop that has the ability to do voltage injection to locate/replace the MOSFETs causing the short. The only sure fire way to correct it. Is the PSU modular? If so when you disconnect the eps 4 pin, do you also disconnect it from the PSU?

My psu is not modular and i also think that it will send power to wires that aren't connectes as well

JrRacinFan · Feb 25, 2022

makuke12 said:
My psu is not modular and i also think that it will send power to wires that aren't connectes as well

Oh ok. Well aside from potentially replacing the motherboard, 1 other you can test is if everything works outside of the case on a cardboard box. My suggestion was going to be if it is modular that could potentially have a short in it.

Nike_486DX · Feb 25, 2022

Most probably cpu vrm went bad (thus by providing the 12v cpu power you are triggering the scp and the psu "clicks" for a split second before shutting down. Usually its easy&cheap (with technical experience ofc) to locate the shorted mosfet on the motherboard and replace it BUT unfortunately there is also a great chance that the cpu was killed by the short (in some cases the 12v goes into the cpu which instantly kills it), its not not 100% guaranteed but you gotta be prepared to replace the cpu since unlike mobo you cant fix them.

makuke12 · Feb 25, 2022

But would pc start then? My pc starts then runs for 10 seconds or so then does it again and then shuts off. Also fans work during that

JrRacinFan · Feb 25, 2022

makuke12 said:
when 4 bin cpu cable is connected pc doesn't turn on but when it isn't it turns on

Which one is it? What you're now describing is totally different behavior altogether.

skizzo · Feb 25, 2022

makuke12 said:
But would pc start then? My pc starts then runs for 10 seconds or so then does it again and then shuts off. Also fans work during that

that sounds like it is trying to POST but fails. It cannot POST with the cable unplugged, because the CPU isn't getting the required power with it unplugged. that behavior would be expected when EPS cables are not plugged in. the POST will basically think there is no CPU installed. I assume same thing would happen if the CPU did in fact get fried from the potential hardware issue others alluded to

on the flip side, it does absolutely nothing if the cable is plugged in and you try to turn on the PC. others pointed out, that could mean a hardware problem and you would need to take it to a professional to at least fix, if not also diagnose and then fix. but actually before that, if possible, it would be a good check to eliminate the CPU being dead as a variable and swap in a known working CPU....if you have one or are willing to find a cheap compatible one on ebay or your countries equivalent of ebay. you could also put your CPU into another known working motherboard to help understand these variables.

what do you use this system for? is this is a purpose built retro system, or is it your daily driver system? I ask because this system is a bit long in the tooth by today's standards. if you want this system for a specific use case then I understand the desire to fix it. but if it is a daily use kinda PC, I suggest you weigh the costs of fixing this system, or investing in one that is a little newer. it may no long make financial sense to dump time/money into something so outdated

Bones · Feb 25, 2022

From what's described it sounds like he's plugging in the wrong one if it has the split 4-4 CPU power plug, most PSU's there days have it.
I've done it before and that's exactly what mine did in how it behaved.

Thing is with a split 4-4 CPU power plug you CAN plug in the wrong one if it's turned 90 degrees from where the socket tab for the plug's latch is, the wrong plug will just go right in as if it's the right one but it's not.
I found the problem and noted I had done that, switched plug ends, made sure it was going in the right way and the system then booted.

OP - Make sure you aren't plugging in the wrong side/half and also be sure when it's in, the little latch/hook is going where the tab for it to lock onto is.

eidairaman1 · Feb 25, 2022

makuke12 said:
So i have this problem when 4 bin cpu cable is connected pc doesn't turn on but when it isn't it turns on. Can someone tell me what can cause this? I think its psu but im not sure.

Swap to a known working psu and report back

It is still called P4

Deleted member 24505 · Feb 25, 2022

imo it's the motherboard. Have the same problem on a p6t deluxe, pretty sure board is kaput. Tried known good psu too, same, guessing his will.

JrRacinFan · Feb 25, 2022

Bones said:
Make sure you aren't plugging in the wrong side/half and also be sure when it's in

Thank you for mentioning this. I was taking a big assumption that OP knew how to hook up a power supply but yes youre right, people will be people and it's pure human to error making an oopsie lol

Durhamranger · Feb 25, 2022

Tigger said:
imo it's the motherboard. Have the same problem on a p6t deluxe, pretty sure board is kaput. Tried known good psu too, same, guessing his will.

I Have a Spare P6T deluxe board and ram free to a good home...

Tetras · Feb 25, 2022

What's the story here? Did you upgrade the CPU? Did the PC stop working and you figured out removing the 4-pin made it work?

Motherboard	GIgabyte GA-965P-DS3
Cooling	Air cooled
Memory	2x2gb DDR2
Video Card(s)	Geforce 960
Storage	500gb + 256gb +60gb hdd-s
Display(s)	Samsung tv
Power Supply	Xilence 500w

Motherboard	GIgabyte GA-965P-DS3
Cooling	Air cooled
Memory	2x2gb DDR2
Video Card(s)	Geforce 960
Storage	500gb + 256gb +60gb hdd-s
Display(s)	Samsung tv
Power Supply	Xilence 500w

System Name	Snow White
Processor	Ryzen 7900x3d
Motherboard	AsRock B650E Steel Legend
Cooling	Custom Water 1x420
Memory	32GB T-Force Deltas
Video Card(s)	PowerColor 7900 XTX Liquid Devil
Storage	20+ TB
Display(s)	Sammy 49" 5k Ultrawide
Case	Tt CTE 600 Snow Edition
Audio Device(s)	Onboard
Power Supply	EVGA 1200W P2
Mouse	Corsair M65 RGB Elite White
Keyboard	Corsair K65 Mini
Software	Windows 10
Benchmark Scores	Avermedia Live HD2

Motherboard	GIgabyte GA-965P-DS3
Cooling	Air cooled
Memory	2x2gb DDR2
Video Card(s)	Geforce 960
Storage	500gb + 256gb +60gb hdd-s
Display(s)	Samsung tv
Power Supply	Xilence 500w

System Name	Snow White
Processor	Ryzen 7900x3d
Motherboard	AsRock B650E Steel Legend
Cooling	Custom Water 1x420
Memory	32GB T-Force Deltas
Video Card(s)	PowerColor 7900 XTX Liquid Devil
Storage	20+ TB
Display(s)	Sammy 49" 5k Ultrawide
Case	Tt CTE 600 Snow Edition
Audio Device(s)	Onboard
Power Supply	EVGA 1200W P2
Mouse	Corsair M65 RGB Elite White
Keyboard	Corsair K65 Mini
Software	Windows 10
Benchmark Scores	Avermedia Live HD2

pc not turning on when cpu 4 bin cable is plugged

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Tetras

System Name	Mini efficient rig.
Processor	R9 3900, @4ghz -0.05v offset. 110W peak.
Motherboard	Gigabyte B450M DS3H, bios f41 pcie 4.0 unlocked.
Cooling	some server blower @1500rpm
Memory	2x16GB oem Samsung D-Die. 3200MHz
Video Card(s)	RX 6600 Pulse w/conductonaut @65C hotspot
Storage	1x 128gb nvme Samsung 950 Pro - 4x 1tb sata Hitachi 2.5" hdds
Display(s)	Samsung C24RG50FQI
Case	Jonsbo C2 (almost itx sized)
Audio Device(s)	integrated Realtek crap
Power Supply	Seasonic SSR-750FX
Mouse	Logitech G502
Keyboard	Redragon K539 brown switches
Software	Windows 7 Ultimate SP1 + Windows 10 21H2 LTSC (patched).
Benchmark Scores	Cinebench: R15 3050 pts, R20 7000 pts, R23 17800 pts, r2024 1050 pts.

Processor	i9-9900K @ 5.1GHz (H2O Cooled)
Motherboard	Gigabyte Z390 Aorus Master
Cooling	CPU = EK Velocity / GPU = EK Vector
Memory	32GB - G-Skill Trident Z RGB @ 3200MHz
Video Card(s)	AMD RX 6900 XT (H2O Cooled)
Storage	Samsung 860 EVO - 970 EVO - 870 QVO
Display(s)	Samsung QN90A 50" 4K TV & LG 20" 1600x900
Case	Lian Li O11-D
Audio Device(s)	Presonus Studio 192
Power Supply	Seasonic Prime Ultra Titanium 850W
Mouse	Logitech MX Anywhere 2S
Keyboard	Matias RGB Backlit Keyboard
Software	Windows 10 & macOS (Hackintosh)

Processor	Ryzen 2600
Motherboard	X470 Tachi Ultimate
Cooling	AM3+ Wraith CPU cooler
Memory	C.R.S.
Video Card(s)	GTX 970
Software	Linux Peppermint 10
Benchmark Scores	Never high enough

System Name	PCGOD
Processor	AMD FX 8350@ 5.0GHz
Motherboard	Asus TUF 990FX Sabertooth R2 2901 Bios
Cooling	Scythe Ashura, 2×BitFenix 230mm Spectre Pro LED (Blue,Green), 2x BitFenix 140mm Spectre Pro LED
Memory	16 GB Gskill Ripjaws X 2133 (2400 OC, 10-10-12-20-20, 1T, 1.65V)
Video Card(s)	AMD Radeon 290 Sapphire Vapor-X
Storage	Samsung 840 Pro 256GB, WD Velociraptor 1TB
Display(s)	NEC Multisync LCD 1700V (Display Port Adapter)
Case	AeroCool Xpredator Evil Blue Edition
Audio Device(s)	Creative Labs Sound Blaster ZxR
Power Supply	Seasonic 1250 XM2 Series (XP3)
Mouse	Roccat Kone XTD
Keyboard	Roccat Ryos MK Pro
Software	Windows 7 Pro 64

System Name	Blah
Processor	Ryzen 7950x
Motherboard	Asrock X670E Taichi
Cooling	BLACK ICE SR2 480,EKWB Quantum Magnitude AM4,D5 Pump,17 CORSAIR SP120 RGB ELITE
Memory	32Gig Gskill 6000 DDR5
Video Card(s)	MSI RTX 4090 LIQUID X 24G
Storage	Optane 900P 480GB,2x SX8200 2TB ,SAM 980 PRO 2TB,2xSAM 860 EVO 1TB,SAM 870 EVO 4TB,SAM 860 EVO 2TB
Display(s)	Samsung Odyssey Neo G9 57
Case	CORSAIR 7000X
Audio Device(s)	Realtek ALC4082
Power Supply	CORSAIR HX1500I
Mouse	Corsair Harpoon
Keyboard	Corsair Strafe MkII
VR HMD	Oculus