HP Compaq Pro 6305 SFF Power Issue

[cna2373]

Good Morning,

HP Compaq Pro 6305 SFF Power Issue

4 pin green = P2, 6 pin=P1 and 4 pin (black & brown) =PWRCPU

What's the issue? The computer will begin to boot for a second and then shuts down.

Power Supply (PS)- I have isolated the power supply and the online test I found shows that it's good. (12+vdc) also, when the PS is isolated and the 6 pin black is jumpered to the 4 pin green it does not surge.

Power Supply connected to the computer- when the 4 pin (black & brown) plug is connected it boots for a second and then shuts down; with the 4 pin (black & brown) plug disconnected the PS surges. If I disconnect the 6 pin plug it does nothing.

Note: The RAM and All other wires and cables are disconnected except for the 2 led lights and power push button, I also changed the bios/cmos battery.

I read that if you pull the 4 pin (black & brown) wire and everything else runs it means there's a problem with the cpu/motherboard. But that doesn't explain why the PS would surge with only the 6 pin and 4 pin (green) wires connected.

Please and Thank You for your consideration and help of my issue.

[Scott1997]

hp 6395 running alma9 linux, no startup, no beeps, no post no boot, no display, power on after 45 seconds cpu fan races, pwr supply good, it will randomly startup after off for days and will work fine. then upon a reboot will not start again from warm start or cold start. cannot get to f2 or f10/f11

removed all external device connections and memory, same no start. used a PCI post diag card to get error codes, card shows pwr ok , upon start displays code of 5E5D - code not listed anywhere. want to find this problem as it seems this is a hp problem as many have this same issue. also changed BIOs battery and reset, same no start.

seems like as it trys to start initial checks are failing - would like to know hp's startup code flow. hp will not help as they say this hp6305 is discontinued item. will not purchase hp again or recommend hp to my company - major engineering contractor

any help would be much appreciated - I don't want to just start shotgunning parts

Scott