Symptoms of a broken CPU in new system? (AMD A8-3870K)

[Domner]

I'm putting together a new HTPC system, and I'm having some issues that are either a case of broken hardware or me being more than usually stupid. Hope someone here can help me figure it out.

I'm using an AMD A8-3870K CPU, a Gigabyte GA-A75M-UD2H motherboard and a pair of KINGSTON 2GB 1333MHZ DDR3 CL9 memory modules. Here is the issue I'm having:

When powering up the system (with just the bare minimum of stuff connected, just the CPU, power, front panel switches/leds, chassi speaker, memory modules and a monitor), I get the CPU fan spinning but absolutely no other reaction from the system. No output on the monitor (have tried both VGA and DVI), no beeps from the system speaker, nothing.

- I have tried with another power supply, a known working power supply from my gaming computer (so should easily be powerful enough for this).
- I have tried with just one memory module at a time, and no memory modules at all as well.
- I have tried a different motherboard (ASUS F1A75-M PRO).

Always the same problem. I'm surprised to not at least get some beeps from the speaker, but I'm just getting nothing at all.

- Have been unable to try a different CPU, or using a separate graphics card.

So am I missing something very obvious here? Would a broken CPU lead to these symptoms with no beeps from the motherboard, or could something else be going on? Grateful for any help, really hate not getting any progress in this.

 

[ShintaiDK]

Maybe silly question. But are you sure the current BIOS on the mobo supports the CPU?

Its extremely rare for a CPU to be broken.

 

[Domner]

Not really, as for both the motherboards I have tested the CPU is only supported with more recent BIOS releases, but what would be the expected symptoms of the CPU not being supported? I guess the no graphic output would make sense given that I'm using the built in graphics, but no error codes from the speaker is a bit confusing to me.

Also, for at least the Asus board the BIOS supporting my CPU was released in October 2011, so I'm hoping it would have at least that recent a BIOS release on board when I bought it.

 

[TakeNoPrisoners]

It could be a broken motherboard too, can you get another CPU that is of a different model to try?

 

[ShintaiDK]

Also, for at least the Asus board the BIOS supporting my CPU was released in October 2011, so I'm hoping it would have at least that recent a BIOS release on board when I bought it.

Wasnt the CPU released around dec 2011/jan 2012?

 

[AtenRa]

It may need a bios update for the CPU.

 

[ericloewe]

Whenever that happens to me, there's always one very easy fix: Connect the processor's auxiliary power connector. It sounds silly, but I thought I'd ask.

Otherwise, if it's not the BIOS, it may very well be a bad processor, since fans running, power delivery OK, but nothing else is typical for a non-functional processor.

 

[Domner]

It certainly could be a BIOS issue, and if that is the case then I guess I will need an older CPU in order to upgrade the BIOS. Very annoying in that case, that both motherboards I have tested would give absolutely no error indication when the CPU is unsupported. Also, just looking at the Asus board if the BIOS is too old to support this CPU then the board would currently be running a BIOS that supports very few CPUs. The 1103 BIOS is required for the A8-3870K, and the only CPUs that require older BIOS releases than that are the A6-3650 and the A8-3850.

 

[Domner]

Whenever that happens to me, there's always one very easy fix: Connect the processor's auxiliary power connector. It sounds silly, but I thought I'd ask.

Otherwise, if it's not the BIOS, it may very well be a bad processor, since fans running, power delivery OK, but nothing else is typical for a non-functional processor.

Have considered the power supply. Have definitely connected the aux power, and I also considered that my (cheap) power supply intended for this build might not be working correctly or might be to weak but I think I have eliminated that possibility by testing with another known working power supply.

So in your opinion the symptoms I see would be typical for a broken CPU? Would a broken CPU prevent the motherboard from booting far enough to even provide error beeps?

 

[Magic Carpet]

Would a broken CPU lead to these symptoms with no beeps from the motherboard, or could something else be going on? Grateful for any help, really hate not getting any progress in this.

To me, it looks like you need a BIOS update. Get a different processor and try. Or send this one back to the shop and get a refund.

 

[Soulkeeper]

You said you've tried a different motherboard and it still didn't boot ?

That's pointing right at the CPU being bad.
I would not be surprised to see a faulty cpu. I don't think it's as rare as some believe specially considering this is a forum where people post problems ...
This is AMDs first wave of 32nm afterall (extremely high voltage to compensate for low yeilds).

The bios versions being too old on both motherboards would be a much more unlikely scenario.

Did you buy this CPU locally ? that'd make it an easy swap

 

[sm625]

Unfortunately llano is not all that common so finding one with which to update the bios could be problematic. If possible I would buy a first generation A4 from someplace that will allow you to return it.

 

[Soulkeeper]

Domner what city are you in ?
If you're in the san diego area i've got an A8-3850 we could swap in.

Also I think fry's will update bios for you for a small fee.

 

[podspi]

You really think it could be a BIOS issue? It isn't like he is trying to put a Trinity-based CPU into a motherboard that only supports Llano (pretend that would fit). The only issue I've ever had with the motherboard needing a BIOS update is w/ Thuban, but again Thuban was a different beast from Deneb.

What is different except the clock speed? In my past experience, if the motherboard doesn't recognize the CPU but still manages to bring it up, it usually just defaults to some very low frequency...

 

[Soulkeeper]

You really think it could be a BIOS issue? It isn't like he is trying to put a Trinity-based CPU into a motherboard that only supports Llano (pretend that would fit). The only issue I've ever had with the motherboard needing a BIOS update is w/ Thuban, but again Thuban was a different beast from Deneb.

What is different except the clock speed? In my past experience, if the motherboard doesn't recognize the CPU but still manages to bring it up, it usually just defaults to some very low frequency...

you've got to be right.

It's likely only needed to report the cpu model name properly during post.
same way old socket A boards did, where they'd work but wouldn't "recognize" newer athlons

Unfortunately I don't think I ran my 3870 in this board (same as his) without first upgrading the bios.
Besides the bios makers likely knew an unlocked A8 was coming before they even shipped the fm1 boards.

his memory might be an issue, but also unlikely

 

[T_Yamamoto]

you've got to be right.

It's likely only needed to report the cpu model name properly during post.
same way old socket A boards did, where they'd work but wouldn't "recognize" newer athlons

Unfortunately I don't think I ran my 3870 in this board (same as his) without first upgrading the bios.
Besides the bios makers likely knew an unlocked A8 was coming before they even shipped the fm1 boards.

his memory might be an issue, but also unlikely

So dos upgrade the BIOS?

 

[Magic Carpet]

You really think it could be a BIOS issue? It isn't like he is trying to put a Trinity-based CPU into a motherboard that only supports Llano (pretend that would fit). The only issue I've ever had with the motherboard needing a BIOS update is w/ Thuban, but again Thuban was a different beast from Deneb.

What is different except the clock speed? In my past experience, if the motherboard doesn't recognize the CPU but still manages to bring it up, it usually just defaults to some very low frequency...

Usually, yes. But, not always. His BIOS might just needs to be re-flashed.

 

[ShadowVVL]

Could be llanos gpu is bad or not working due to bios.Did you try putting a desecrate gpu in?

 

[Kristijonas]

I had the same CPU 3870 and the very same gigabyte ud2h a75 motherboard. Worked flawlessly. And this motherboard is made for llano CPUs so it can't be a BIOS issue either. Maybe both of your power supplies are corsair? It is known (and happened in my case) that at least corsair cx 430w doesn't work with integrated graphics only setups. Perhaps bad RAM ? I used 2x4gb @ 1866 myself, so it's not a frequency problem.

 

[Soulkeeper]

So dos upgrade the BIOS?

this gigabyte board has a feature to upgrade from within the bios
you just put the image on a usb flash stick, very nice
I upgraded mine to the latest beta bios the other day

 

[Elixer]

this gigabyte board has a feature to upgrade from within the bios
you just put the image on a usb flash stick, very nice
I upgraded mine to the latest beta bios the other day

That is a great feature.

For what it is worth, I had a CPU go bad, and the motherboard didn't throw any POST errors or anything, it just wouldn't POST. Just fans spin, and that is all.

Usually, if you need a BIOS update, it would still POST, but give you the wrong info about your CPU.

 

[Pretty Cool]

A dead cpu would not produce any beeps on the motherboard. On the other hand, having no memory installed should. Do you need to attach a little speaker to the motherboard as I did not notice one in the picture? It does not matter anyway as would probably need to swap the processor to be positive either way. Perhaps look for a local retailer that has a reasonable return policy.

 

[Domner]

I had the same CPU 3870 and the very same gigabyte ud2h a75 motherboard. Worked flawlessly. And this motherboard is made for llano CPUs so it can't be a BIOS issue either. Maybe both of your power supplies are corsair? It is known (and happened in my case) that at least corsair cx 430w doesn't work with integrated graphics only setups. Perhaps bad RAM ? I used 2x4gb @ 1866 myself, so it's not a frequency problem.

Interesting, I was actually going to use a Corsair CX 430W for this build, so that is one of the power supplies I'm using. The other one I have tested is a Zalman though.

 

[Domner]

A dead cpu would not produce any beeps on the motherboard. On the other hand, having no memory installed should. Do you need to attach a little speaker to the motherboard as I did not notice one in the picture? It does not matter anyway as would probably need to swap the processor to be positive either way. Perhaps look for a local retailer that has a reasonable return policy.

I do need to attach a separate speaker yes, and have done so. Have bought the CPU and most of the other items from an online retailer, which is why I really want to know which component is broken before starting a process of returning anything...

 

[Soulkeeper]

Why not take the CPU to the local pc shop and ask them to test it ?
i'm sure they've got an fm1 board they could swap it in real quick