MSI Z77-G43 - Request to identify and replace MOSFET transistors.

Hello. I have a motherboard from a MSI Z77-G43 desktop computer with short-circuited NIKOS transistors:

P0803BD
P0503BD

I found a counterpart to the first one

IRFR 3707Z or IRLR 8729PBF, unfortunately, it is difficult to find a datasheet for the second (P0503BD). I found a description like this:

VDS (V) 30V
VGS (+ -) 20V
ID (A) 55
RDS (on) 5.8 m?
VGS (th) max 7.8
Qg (nC) 3
Qgd (nC) 1780

I found as a replacement:
JPB055N03LG but I don't know if it would be appropriate. I am asking for any suggestions or proposals for another replacement.
I have one more question, while desoldering (then I have a hot aira with an ordinary soldering iron) I damaged the legs on four transistors and I do not know whether to replace only these or the entire section (the rest in the transistors section).
Thank you in advance for each answer.

So I would like to ask, what are the applications of these transistors on the motherboard?

Added after 10 [minutes]:

For the latter, in my opinion, a good IRFR3707ZPBF would be

IRFR3707ZPBF No >> Has too much Rds, almost 2x as the original.

* "works as" heater "

For example datasheet of the popular 50N03, 55N03 Link
- good RDS and other parameters
- an important field parameter taken into account when replacing it
Input Capacitance Ciss
Output Capacitance Coss

These field Nikos stand on MSI plates
-or in a dc-dc converter (4 + 1 phase) on the UT501, UT501p CPU power driver
* UP1625P chip (uP1625P) / for 2 phases UP6282
* 2x P0503BD in the upper branch and 1x ?0803BD in the lower branch

* solution from the Z68A-G43 board


-or in RAM power supply
* no driver, powered from CPU part

(' ') (' ')
As you mention in the field phase> change all: 2x P0503BD and ?0803BD
- so that there are no "surprises"
-measure half of the remaining phases


Driver



uP6282p



ps
Org. Nikos Field Fields on (aliexpress) is 0.7 $ / pcs. when buying min. 5 pcs. (flight)
* long waiting for delivery (min. 20 working days)

Hello. Thanks for the copy. At the outset, I want to add that I am not too advanced. To my colleague LISEK, how well do I understand, I can use JPB055N03LG for the second (P0503BD) about which I wrote in the first post (it is available on TME) ?. Please tell me which of these two IRFR 3707Z, IRLR 8729PBF parameters would be the closest to P0803BD (both are available on TME). I haven't bought on aliexpress yet, maybe I'll try one day.
What else should I test apart from the field-effect transistors in the remaining phases?
The disc was damaged after a lightning strike near me, the radio Internet receiver, router, all televisions connected to the home network and, among others, the motherboard were burned. The RTL 8111 chip was burned on the board, which I desoldered because I thought it was causing the short circuit, but unfortunately the board continued to show a short circuit (automatic power supply shutdown). I found a short circuit on one of the phases on the transistor, so I am asking.

After lightning, it could be a lottery.
You found a short circuit, maybe replacing one phase will help.?
- if it doesn't start >> look for a new album.

Look for parts on https://en.aliexpress.com

Important RDS parameter, from datashhet IRL8729

May be.
Look at the site Link_ uk.farnell_ N-channel

One thing is that, apart from the motherboard, nothing has been damaged (PSU: Crucial CS650M; Proc: Intel Core i5 3570k; RAM: Kingston HyperX (2x4GB @ 1600 MHz / 9CL, Asus Radeon 280x directcu ii) all components continue to work (a theoretically, they could have been damaged, as you wrote "after lightning is a lottery") on another weaker board Could burning the RTL 8111 chip damage the transistor in the power section?

Please tell me what the differences can be in the parameters when changing into:
Input Capacistance-Ciss
Output Capacitance- Coss in pF ?.

Not more than 15% of the original org. Capacity value. transistor.

Hello. However, I will order transistors on alliexpress, the fact must wait a bit, but the original is the original. The computer is running on a weaker board and I can wait. He will contact you as soon as the package arrives and whether the album comes to life or not. Thanks bye. Best regards.

Hello, after a long break. I replaced the transistors in the PWM 2 section (P0803BD and P0503BD) and one in the PWM 1 section, which showed a short circuit (first from the left in the photo below), the board starts, but after about five minutes the replaced transistor (P0803BD) gets a short circuit again. I replaced it with a new one, but the situation repeated, only the one in the PWM1 section gets a short circuit, I will add that the transistor does not even show increased temperature. Something causes a short circuit, but I don't know what?
The signal from the transistor goes to the uP6282AD to the 14th and 15th pin. I don't know if this is the system that controls the entire section, or if I try to resuscitate the record or let go. What can cause a short circuit on the above-mentioned transistor, what else to check. Thank you in advance for your answer.

I suspect you have something to do with the control of the owgo damaging field
-needed oscilloscope, waveforms on the input
- or general cargo in its vicinity

Quote:

The CPU VRM is composed of:
-4 phases for the CPU (cores) (4 coils + 8 mosfets)
-1 phase for the memory controller embedded into the cpu (1 coil + 2 mosfets)

________________________________

On MSI boards for AM3 + (AMD 990FX + SB950 chipsets) to power 8 + 2 phase cpu (Buldozzer)
- two systems from Upi Semiconductor uP1601P and uP6270BQ are responsible for supplying voltage.
* no data and datasheet


- DrMos was used in each (of the 10-phases)
FDMF6704V Link



On MS-7699 motherboards with RS780L (truncated version AMD 780G - F of built-in graphics kernel 350 MHz (compared to 500 in old version)
- CPU power supply (additional 8-pin plug) was made as: 4 + 1
There were 2x 2SK4212A and 2x? 2SK4213A Renesas (NEC) for each phase
Two uPI Semiconductor uP6282AD chips were used for the 4-phase control
* (this driver, which has two incoming channel from the PWM controller and two output channels, with the doubler phase).

For a single (+1) strip, a simpler ver. CPU NB Core ?, as uPI Semiconductor uP6281S8 driver,
The uPI Semiconductor uP1601P used to be the voltage controller



The above-mentioned field and uPI Semiconductor uP1540T were used in powering RAM.
uPI Semiconductor uP0109 as memory terminal security

Hello. Unfortunately, I do not have an oscilloscope, my knowledge is rather not advanced. If I understood this section correctly, the P6282 controls and in its environment I should look for any damage. Can the P6282 chip itself cause a short circuit in this transistor?
Please tell in simple words where would you look for damage.
I would have one more question where to find the schematic of this album. Thank you in advance for your answer. Best regards.

This is my opinion.
Forget about SM
* how to look for it only at the disc manufacturer (e.g. Foxcon)
* a small vademecum on VRM per MB Link


A plate in China
MSI MS-7758 Z77A-G43 Motherboard 1155 DDR3, Intel Z77 chipset
* $ 128.88 + $ 25.00 Shipping

Gigabyte boards on this chipset from $ 60
* ga-z77p-d3 ddr3 lga1155


MSI Z77A-G4 (MS-7758)


On the MSI MS-7751 motherboard, also the Z77 chipset
-stby is uP1712p
-controller for cpu voltages is uP1618
uP1513p RAM controller
- kbc F71889AD