Computer Help forum

General discussion

Computer turns on for a split second then turns off.

Built my computer about 2 years ago and have had zero issues with it. Had the computer on doing nothing when it turned off for no reason. Hit power button to turn back on and PC blinks on for fraction of a second and shuts down. There is no beep. It does this repeatedly. I have replaced the PSU, motherboard, CPU and switched out the ram with no changes. I am completely baffled. Please somebody help. Thanks in advance.

Post a reply
Discussion is locked
You are posting a reply to: Computer turns on for a split second then turns off.
The posting of advertisements, profanity, or personal attacks is prohibited. Please refer to our CNET Forums policies for details. All submitted content is subject to our Terms of Use.
Track this discussion and email me when there are updates

If you're asking for technical help, please be sure to include all your system info, including operating system, model number, and any other specifics related to the problem. Also please exercise your best judgment when posting in the forums--revealing personal information such as your e-mail address, telephone number, and address is not recommended.

You are reporting the following post: Computer turns on for a split second then turns off.
This post has been flagged and will be reviewed by our staff. Thank you for helping us maintain CNET's great community.
Sorry, there was a problem flagging this post. Please try again now or at a later time.
If you believe this post is offensive or violates the CNET Forums' Usage policies, you can report it below (this will not automatically remove the post). Once reported, our moderators will be notified and the post will be reviewed.
Collapse -
"Make it smaller."

In reply to: Computer turns on for a split second then turns off.

You don't need a case, drives, or much else for a power up test. If you start small such as PSU, motherboard+CPU+HSF and one stick of ram you usually get a power up. If not, the problem is in those parts.

Again, no case required. Just some cardboard to set the parts on.

Collapse -
Tried that...

In reply to: "Make it smaller."

I replaced all of the parts you mentioned with brand new ones and still had the same issue.

Collapse -
Then you still have a dead/badly configured part.

In reply to: Tried that...

I've lost count how many times the owner didn't start small on cardboard. But new parts means warranty. Ask them what they want to change out.

Collapse -
Bad video card but still have issue

In reply to: Then you still have a dead/badly configured part.

The computer isn't in the shop, i'm working on it myself. The one thing I didn't change out with the video card and it looks like that was the issue as far as the computer actually starting. Computer started right up after installing new video card. But it won't post. Screen is black. The error indicator lights on the motherboard are showing a solid red light for the RAM and blinking for CPU. Tried each of the four sticks individually with the same result.

Collapse -
No shop.

In reply to: Bad video card but still have issue

New parts have a warranty so you use that.

I wish you would detail what this PC is made of. Sometimes we have an option for no GPU. Also the number of times I find the CPU isn't supported is far too high. In some cases the CPU is supported but ONLY after the BIOS is updated.

Collapse -
Re: no boot

In reply to: No shop.

Your problem was: auto turn off in one second. Solved by changing video card. Now power stays on.
Your problem now is: No post. Worked fine for 2 years.

Then it's time for the cardbox test (no case, no hard disk, 1 stick of RAM; only PSU, motherboard with CPU and RAM, keyboard+mouse connected, GPU if no video on mainboard). If that fails, it's one of those components.

Collapse -

In reply to: Bad video card but still have issue

Your not following directions.

Your keeping the machine/parts a secret.

Good luck getting help from the forums.

Take the machine to a service counter and let them fix it.

Collapse -
Here you go

In reply to: Post

Intel I5 6600
MSI Z170A Gaming M3
Nvidia GTX 970 OC
16 GB Corsair Vengeance DDDR4
Sandisk SSD
Hopefully that gives you what you need although I don't see how it's going to help. Now that I've given you the information that you require could you please take the time to actually read what I post. Because it's painfully obvious that you're not. Telling me to bring it to a service center is no help at all. I could have done that without you. Let's try and stick to the problem at hand.

Collapse -

In reply to: Here you go

Collapse -
No post

In reply to: Here you go

Since your cpu has an igp plug the monitor into the mobo and remove the gpu.....test.

You left out the make and model of the psu.

You don't need more than one stick of ram.

You don't need a disk connected.

Collapse -

In reply to: No post

850 Watt Antec. I have performed the cardboard test. I know that method and I was thinking about a short circuit somewhere as well but that's not the case.

Collapse -
Next most common cardboard test fail reason?

In reply to: PSU

The CPU isn't installed correctly.

I take it as truth your claim these are all new parts so is there any part that isn't new as in just a week old? Maybe the problem parts were not swapped out?

Collapse -

In reply to: PSU

Tell that you have the mobo sitting on a piece of card board.

Tell what is connected or installed on the mobo.

Popular Forums

Computer Newbies 10,686 discussions
Computer Help 54,365 discussions
Laptops 21,181 discussions
Networking & Wireless 16,313 discussions
Phones 17,137 discussions
Security 31,287 discussions
TVs & Home Theaters 22,101 discussions
Windows 7 8,164 discussions
Windows 10 2,657 discussions


Best Black Friday Deals

CNET editors are busy culling the list and highlighting what we think are the best deals out there this holiday season.