Z690 Pro-A VGA troubleshooting - PSU giving 8 pins that spread to two 8 pins on the graphics card

thepipospip153702d2

thepipospip153702d2

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I'm having trouble getting my system to display after buying a prebuilt computer with Z690 A mobo and intel i7 12700 CPU & gigabyte RTX 3080 oc 10gb. Since it turns on but the card don't display anything I had removed the card and tried to update the BIOS using the USB Flashback method.

although it seems like it is updating and flashing red light, the computer turns on after it seems to stop flashing
I have seen people say it should go off after updating but instead it powers on and the VGA debug LED remains on. I've tried clearing the CMOS (both by shorting the JBAT1 pins and removing the CMOS battery), but the issue persists.

I think it should at least use the dedicated card and display something but it doesn't
ps: system has no storage drives

I am somewhere where there are no technicians to troubleshoot it so I need help figuring things
 
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update
I figured out that it is normal that the computer turns after the bios flash process
I checked the PSU and it seems that it is giving 8 pins that spread to 16 then two 8 pins on the graphics card
The Thermaltake manual suggests having a direct two 8 pins from the power supply to the card

I am wondering if giving the card 16 pins from the PSU will solve the VGA debug light issue and post
 
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If it was pre-built, did it not work out of the box? Also, some pre-built systems use a custom BIOS and using the Flashback method could have screwed something up.
 
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What's the exact PSU model? Not only do you need two seperate 8-pin cables for the GPU, the PSU also needs to be of adequate quality and rated wattage to cope with such a GPU. The PSU model is written on a sticker on its side.

When using only one cable and two plugs on it, the other side of the cable is still a single cable coming from the PSU, so this cannot double the cable cross-section (for half the resistance and twice the conductance) like a second cable does. It only slightly lowers the overall contact resistance on the GPU side, which is usually negligible anyway.

pcie.jpg
 
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citay said:
What's the exact PSU model? Not only do you need two seperate 8-pin cables for the GPU, the PSU also needs to be of adequate quality and rated wattage to cope with such a GPU. The PSU model is written on a sticker on its side.

When using only one cable and two plugs on it, the other side of the cable is still a single cable coming from the PSU, so this cannot double the cable cross-section (for half the resistance and twice the conductance) like a second cable does. It only slightly lowers the overall contact resistance on the GPU side, which is usually negligible anyway.

View attachment 197031
Click to expand...
thermaltake toughpower grand rgb 850w
are you saying it should be able to post even with 1 cable from the PSU?
why didn't it post from the dedicated GPU when I removed the rtx and updated the BIOS?
 
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thepipospip153702d2 said:
thermaltake toughpower grand rgb 850w
Click to expand...

This PSU has even three seperate PCIe power cables (with two plugs daisy-chained on each). You should see three red headers on the back of the PSU for them.
Of course, this being a used pre-built, the cables that were not used might not be included anymore.

thepipospip153702d2 said:
are you saying it should be able to post even with 1 cable from the PSU?
Click to expand...

No, this is not a given, the graphics card might detect this and not want to work. It depends on the card.

thepipospip153702d2 said:
why didn't it post from the dedicated GPU when I removed the rtx and updated the BIOS?
Click to expand...

You need to check the EZ Debug LEDs above the 24-pin ATX header. They will give a hint. Did you try both outputs on the board, HDMI and DisplayPort?
 
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update guys
bought and received additional cable and the problem is still there
The motherboard is on VGA debug light whether the card is connected to the PCIe or not
No post from MB on its own too


can't DisplayPort cuz I have no cable
 
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thepipospip153702d2 said:
bought and received additional cable and the problem is still there
The motherboard is on VGA debug light whether the card is connected to the PCIe or not
Click to expand...

You mean additional PCIe power cable, right? Don't bother testing without the cables hooked up to the card, that will only guarantee the VGA LED.

VGA LED, then probably even the DisplayPort outputs won't show anything. Can you borrow a different graphics card for a test?

Did this PC at any point work normally? I mean, you bought it used, so the first thing i check is if it runs properly, and if not, the seller hears from me.
 
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Let's recap again
the light is on even without the video card plugged
There is a chance that my CPU is I12 700 which I think has a dedicated GPU
I saw your reply https://forum-en.msi.com/index.php?threads/white-vga-light.385676/post-2188303
And I think it is the next thing to try

I had observed that the MB struggles before lighting the VGA white light
it seems like it pushes hard to post because I can hear an increase in the speed of some fans for a second and then the light turns on
 
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The fans being "boosted" during early boot can be normal for MSI boards, that doesn't indicate a problem.

If your CPU is an i7-12700 (no -F at the end), it would have internal graphics, and it should not show the VGA LED with no GPU installed. What you can try, take out / disconnect any drives (SSD etc.), sometimes a problematic one can cause the VGA LED too.

You can test the 3080 in a different PC, and check if it needs this update: https://nvidia.custhelp.com/app/answers/detail/a_id/5233/
Different one than for the old GPU from that thread you linked.

Or you test with a different GPU in this system.

You don't seem to be overly concerned about such issues on a used PC? I've just looked at the eBay page, it lacks in description of all the components used, it says 3070 not 3080, and the seller, just three feedbacks?? I can already see him ghosting you when you cannot solve the problems easily and try to ask him what's up.

The board seems to be this, https://www.msi.com/Motherboard/PRO-Z690-A-DDR4/support
So don't get the BIOS update for the DDR5 version of the board when you try the Flash BIOS Button.
 
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I didn't want to bother you with all of that
I bought it from the US and I am in North Africa
shipped it to me using sea freight for budget reasons which took 30 days during which the return window was closed
Before I received it I had done some research
I used the serial number from the pictures and sent it to Ibuypower to get the specs they sent me the full invoice
This is where I noticed that none of the parts listed in the invoice conform to what is listed on eBay although it's the same name person that is why I'm not sure even about the CPU because in the invoice there's no such CPU, the one that is listed there is a 12700k
but the seller on eBay swears that the desktop was working and that he only had to remove the m.2
What confuses me is that everything looks clean it seems like a recently built desktop or a put-aside one
I can't give up on it because I spent all my money on it so I am just taking my time to learn more about this stuff and try my best before I start searching for a repair place
I hope it works after all or at least that the video card works so I can sell the parts and return some of the money
 
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Well, you gambled a bit much there, shipping a PC from an unknown seller with no reputation, from a foreign country, with no option to return it or do anything about it when there's a problem...

That's how people can be gotten sometimes, the price is not low enough for it to obviously be a scam, but just a bit lower than usual, to override some of the common sense, faced with what looks like a great bargain. I mean, just by searching for "12700K 3070" on my local eBay, i find that the cheapest ones start from over 600 EUR (similar to USD). So US$500, which i think yours was, from such an unknown private seller, it's already risky-sounding to me. Who knows what's wrong with it. Also, why would he take out the SSD? That's just a convenient way of not having to show that it works, and not being able to easily check it within ten minutes of receiving it. If you give him negative feedback, he'll just create the next burner account...

What you need to do now, test parts in a different PC to see if they work properly there, and/or borrow known good parts from another PC to test in yours.
 
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