Thank you for being a valued part of the CNET community. As of December 1, 2020, the forums are in read-only format. In early 2021, CNET Forums will no longer be available. We are grateful for the participation and advice you have provided to one another over the years.

Thanks,

CNET Support

Question

PC powers on: lights, fans, graphics card, but won't boot

Apr 8, 2016 10:23PM PDT

HP Pavilion
AMD Phenom II X4
Windows 10 Pro
120GB SSD & 1TB HDD
GTX 750ti
3 Extended Monitors

I had been using my desktop flawlessly for about 2 years. A week ago, my desktop started acting a little strange. Some times it boots up just fine, and some other times I can see the power-light on, fans spinning, graphics card fan spinning, optical drive pops out, etc. but it's not showing the BIOS splash screen or booting into windows. It does that whenever it wants. If I turn on the PC, there's a 50/50 percent chance that it will boot up just fine; on the other hand, the components might power on but the PC won't boot into windows. Once it powers on though, I can use my computer for as long as I want without it shutting down on me, or causing me any problems; however, when it doesn't boot up I can spend hours trying to get it to boot up. Has anyone had a similar problem. The components are all turning on inside the PC; I've even reseated the RAM modules and graphics card. I'm really lost here.

Discussion is locked

- Collapse -
Answer
run with one monitor
Apr 8, 2016 10:28PM PDT

try running it with one monitor and see if you are having the same problems. what is the full model number of the hp?

- Collapse -
I've tried that already
Apr 9, 2016 12:38AM PDT

It makes no difference whether I use one monitor or three. Sometimes it boots, sometimes it doesn't. I'm not getting any beeps from the PC either. I've been using the same setup for years too. All the components seem be getting power all the time, it just doesn't work all the time.

- Collapse -
(NT) please answer all of my questions
Apr 9, 2016 7:32AM PDT
- Collapse -
One monitor causes the same problem
Apr 9, 2016 8:12AM PDT

HP Desktop PC Pavilion p6720f
AMD Phenom II X4
Windows 10 Pro
120GB SSD & 1TB HDD
GTX 750ti (300W recommended)
3 Extended Monitors
450W PSU

- Collapse -
Answer
Re: boot problems
Apr 9, 2016 1:43AM PDT

Replacing the motherboard should solve this issue. Commonly, after 2 years, it's worth considering to replace the CPU and possibly the RAM also, to be fully up to date.

- Collapse -
You might be right, but it's still really weird to me
Apr 9, 2016 8:50AM PDT

Nothing like this has ever happened to me, and that's why I'm trying to research as much as I can about this problem from other people for feature reference. I've never had a PSU, motherboard, graphics card, RAM fail on me. That's why I don't know what symptoms to look for. I always thought either the PC worked, or it didn't. This computer; however, works great (like I mentioned in other posts) whenever it's booted into windows. I can watch 4k video, play games, use Photoshop, After Effects, etc. It doesn't shut down on me or anything. Are those some of the symptoms of a possible damaged component as well? The fact that it works great, but on the next reboot it just won't boot into windows until it decides to do so? My simple mind would tell me that I should have random shutdowns all the time at some point right?

- Collapse -
Answer
what boot device?
Apr 9, 2016 7:20AM PDT
", optical drive pops out, etc."

if that happens when you try to boot, then reset your BIOS to boot from the SDD or HDD, whichever has your OS on it.
- Collapse -
I probably should have explained that a little better
Apr 9, 2016 8:28AM PDT

The booting order of my devices is fine. What I meant to say is that even when it decides to not boot into windows (sometimes it boots just fine and performs flawlessly until the next time I turn the computer on) I'm able to push the optical drive's button and pop it out because it is getting power (I can visually see all the components inside the PC running). The crazy thing is that once the computer is on it never shuts down, monitor does not flicker, nothing. My problem is when turning the computer on. It's a coin toss whether it will boot or stay in that running state without booting every time I turn it on.

- Collapse -
Look in BIOS, underclock the CPU, see if that helps
Apr 9, 2016 11:40AM PDT

If it does, but still some problems, but fewer, then check for heat problem.

- Collapse -
Answer
This sounds like our old issue called BAD CAPS.
Apr 9, 2016 10:15AM PDT

While the caps may not be bad as in what you read on the web if you google BAD CAPS, the symptom is close enough or same in my view. Which is random start up issues.

The cause is simple from our old issue BAD CAPS to aging of Electrolytic Caps. After a few years these parts are worn and for a motherboard no tech will replace unless it has the BAD CAPS physical flaws. As to the PSU, that could be the cause too as you need about 50 to 100 percent more capacity so it will last more than a few years. That capacity shrinks over time due to the aging I noted.

- Collapse -
That makes a little more sense
Apr 9, 2016 11:42AM PDT

I was planning on getting a 600w PSU anyway. If I ever decide to fix this PC instead of investing on a new one, would an after-market PSU fit my HP stock tower? How about the motherboard? Would I have to get the same motherboard, is it one of those deals where the motherboard is married to the operating system and components because it's OEM? I'm guessing same motherboard just to save headaches right, since I can reuse the RAM, GPU, SSD, HDD, etc.

- Collapse -
You are in luck, that's a standard ATX case and motherboard
Apr 9, 2016 11:49AM PDT
- Collapse -
I'm sorry why is that?
Apr 9, 2016 3:26PM PDT

Are standard ATX cases what most after-market PSU fit into?

- Collapse -
(NT) Yes. Figure 99.99% of the time.
Apr 9, 2016 4:18PM PDT
- Collapse -
Good to know
Apr 10, 2016 11:01AM PDT

Will definitely upgrade at some point for peace of mind

- Collapse -
Let's see what that costs.
Apr 9, 2016 12:38PM PDT
- Collapse -
Let's see what that costs.
Apr 9, 2016 6:10PM PDT

I had a similar problem. Tried all the sugestions and nothing worked.
Replaced the cmos battery and problem reslved.

- Collapse -
I'll definitely try that first
Apr 10, 2016 10:55AM PDT

I would kick myself if I go through the trouble of repairing my PC, and not try your idea first. Specially since the batteries are a couple dollars at my local electronics store.

- Collapse -
Answer
I finally found the culprit, thank you for all the answers
May 30, 2016 6:08PM PDT

After replacing one of the RAM modules, the computer has been running great without booting problems for more than a month. The motherboard, power supply, other ram modules, etc. are all seem to be doing OK. If the same thing happens to one of you, and you don't feel like investing money on the Desktop anymore by replacing major parts, just check the RAM modules on by one.