FriedFred, yes i have one, will rig up a connection point and give it a try.
Found this on youtube- good explanation of power voltage rails sequence.
Also got a working e7450 from ebay- so can remove its screen and try on the faulty unit.

[url]https://youtu.be/56FX6UCsab8?si=PRcd-Tnpp_HDpFLs[/url]https://FriedFred, yes i have one, w...> [url]https:/

ok 1 of the boards got fried, was chasing the missing 3.3v and 5v run voltages shutting down. Was looking around pq200 and pq201 for the 1.35v supply when one of these blew up in spectacular fashion full on flame. So reckon pu11 or one of these mosfets was responsible- by being shorted- might come back to this one later. onto 2nd board now.

So got a sata cradle and hooked the hard drive in it and checked files are reading ok on a working machine. So hard drive us good. So my question is why i would be losing both 5v run and 3.3v run voltages at the same time if they are driven independantly.

FriedFred- checked around all inductors= no shorts. Checking voltages on 1st stage of PM Table = Good, 2nd stage of the PM Table ie 3.3v_sus and 1.35_mem= ok on power standby BUT when power button pressed both of these voltages disappear. No shorts to ground on these.

Trying to learn laptop repairs, looking to be guided/mentored on my journey.
Info - I have 3 boards, 1 which i believe was a working unit and 2 bought faulty to try and repair- Only after i purchesed these did i realise the processors were soldered in place- Duh.
The working unit was used with External monitor via display port output to hdmi monitor with adapter (so i have no laptop display). These were put away a few years back and now i have time to try repairs on them.
Ok So when i power up using dell psu without the memory installed i get the bios led flash code= 1 solid...

Auld_Tinker here.

I am kicking at the door of retirement age now.
I have been in electronic engineering industry all my life. Not in design or programming but in the setting up of systems in the security sector, CCTV, Intruder, Door Access, Fire - Mainly Cctv systems.
I have kept up with technology after getting my Diploma in Electrical and Electronic engineering (1983- Wow time flies).
I had a spell in my hobby of building PC's from scratch- (Windows XP days - even used 3.1) to find out what it was all about hardware and software. Have used fibre and have knowledge...