danny1ro
Member
Last Activity: 04-02-2025, 08:58 AM
Joined: 06-17-2021
Location: Bucharest
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Got help from Mike on another forum, the chip is RT8068A, in case someone is also searching. -
Component identification - HP elitedesk 705 g4 board
Hello,
Can someone please help me identify a component that I have on a board made by HP? It's from an EliteDesk 705 G4 mff system. The component powers a coil that goes to the momery and it only gives me 0.7 volts. Please see attached image.
Thank you! -
Thanks, indeed it was. My next one is a B660 which doesn't start... we'll see when I get around to it.Leave a comment:
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Thank you for the help guys, the motherboard is fixed and nothing caught on fire
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It was that little chip that controller the mosfet, too bad I had to burn a new mosfet and a cpu to learn this.
The low resistance I was measuring is ok.
On to the next one!Leave a comment:
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Hey guys,
My vrm chip finally cam from china and I soldered it on the board. It's an ISL6625ACRZ.
Measuring resistances on the mosfets I still think I'm getting some weird readings.
Case 1- measuring without processor in socket:
- high side source: 99ohms
- low side drain and source: 99 ohms
The gates measure 2 - 3 kohms.
Case 2 - with processor:
- high side source: 0.7 ohms
- low side drain and source: 0.3 ohms
Somehow this seems a bit low to me, but the weird thing is that I am getting this on all the phases...Leave a comment:
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That's by far the best resource I came across that explains a VRM. Now I understood what each of the components does. I looked up why N channels are there and cleared that one out as well. Now all I have to do is wait for that IC to arrive and hopefully not blow another CPU
Thanks again for all the help!Leave a comment:
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You are correct, the mosfet is RA88 and is an N channel one. Why is it an N channel, and why do I have the other two, which are also N channel?Leave a comment:
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Yes, not checking the gates of the N channel mosfets was my mistake.
I will test to see whether that pon can help me get at least a quick activation in the VRM, so that I don't risk frying another cpu. It's difficult when you don't know exactly what you're doing.
To this end, l understand that the 1.2v given to the cpu is a direct result of the high side mosfet activating in pulses. This means that some voltage that passes the high side mosfet will be the voltage that reaches the cpu, smoothed out by the capacitor and choke. If what I said is correct, what is the purpose of the N channel...Leave a comment:
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Testing motherboard VRM without CPU
Hey guys, I'm new here and I'd like to say thanks for all the knowledge on this forum first of all.
I am learning electronics repair, been fixing GPUs and laptops mainly until now, and I'm slowly trying to fix desktop motherboards now.
I had a few successes until now, but I messed things up with one of my recent attempts, namely a Gigabyte H410M S2 with which I burned my test cpu.
I had identified a mosfet which was burned, removed it, cheched for shorts and I didn't find any.
When the new mosfet came, I put it on the board and checked for shorts again and didn't find any.... -
Re: Need help in identifying a component on a GPU
thanks, I think I found the right part on aliexpress, but I'll try to put the old one back there.Leave a comment:
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Re: Need help in identifying a component on a GPU
it will, only a bit o plastic on the side is broken off. I'll give it a tryLeave a comment:
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Re: Need help in identifying a component on a GPU
that would leave me with 0.2, which is about close to that 0.17 I saw in the specs for the model you mentioned.
would it be safe to use again the component which has a chipped corner? if not, I found new ones on aliexpress, but it will be a long wait until I get them.
thanks again for the help!Leave a comment:
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Re: Need help in identifying a component on a GPU
I also measured both now and the readings for both of the components are 1.2 on the "200" scale of my multimeter. Would you consider that the broken part is still usable?
Thank you!Leave a comment:
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Re: Need help in identifying a component on a GPU
Thanks for the reply.
I did search for the component in some databases, but I found multiple thinks listed under the letter "K".
The table I looked at is at the following link: [url]https://smd.yooneed.one/code4b00.html[/url]
I don't know how to measure a fuse, but I will look for a tutorial. Also, when you say to look up size and code, what other code can I look at?
Thanks!Re: Need help in identifying a compo... I did searchLeave a comment:
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Need help in identifying a component on a GPU
Hello everyone,
I have searched the forum for a boardview that would help me identify a component on my Gigabyte rx580, but no luck so, here I am with a request for help.
The story is simple, I wanted to dust it off and my father was near the compressor and he offered to do it, but somehow knocked or blew off a component. Now I'm trying to find what that component is, so I can put it back in its place. I found the one that was there, but it has a chip on one of the corners, with some layers inside showing.
I looked around the board and found another one just like it,... -
Re: New Members - please post your introductions here
Hey guys! I'm here because my father blew off a component on my RX580 with the compressor, while he was dusting it
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