PC won't boot unless I reset CMOS

ItsRapidDave

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Specs:

OS: Windows 10 Pro Insider Preview 64-bit
CPU: AMD FX-8350 @4GHz
RAM: 8GB Corsair DDR3 @669MHz + 16GB Patriot Memory DDR3 @800MHz
Motherboard: Gigabyte GA-990FX-GAMING
GPU: ATI R9 390 8GB
Storage: 2x120GB SSD, 240GB SSD, 500GB HDD

Okay so I've posted about this before but I think the thread is too old now.

Whenever I want to boot up my PC, I have to reset the CMOS (There's a button on the motherboard that does it)

If I don't reset the CMOS, the PC will freeze in post. Nothing is responsive at that point.

When it does successfuly boot (via reset CMOS) I get asked if I want to Restore Optimised Defaults then boot/reboot or to enter BIOS. If I enter BIOS and change stuff (Or don't), the PC will again freeze on post. I can only launch optimised defaults then boot.

I've swapped the CMOS battery for a new one, changed nothing.

I've fiddled and changed the RAM around, this has had no effect.

I've disconnected all the storage devices before boot, this also has no effect.

I've tried updating the BIOS, this changed nothing either.

I've even contacted GIGABYTE and they have no idea what to do either.

The motherboard is fairly new, since September 2016 I think.

Any help would be greatly appreciated.
 
Solution
Get a replacement what, motherboard? We haven't established there is anything wrong with the motherboard. Replacing the motherboard may end up being a bunch of hassle for zero returns. I would suspect any AM3+ board to behave relatively the same given the mixed RAM situation.

You are running mixed RAM modules. No AMD configuration specifically supports this that I am aware of, however Intel does allow dual-channel, up to a point, under those conditions.

If you fine tune the timings and voltage on your current configuration, you may find it is mostly reliable - Provided there is a set of timings that work.
One more thing to check and try. Are you on the latest version of the bios? If not, update the bios to see if that resolves the issue. If not, I think you need to find your receipts for the board and arrange a warranty exchange for the mobo with Gigabyte.
 
I'm not sure this is related but it could be. Apparently the GigaByte mobo with "GIGABYTE UEFI DualBIOS™ Technology" can boot two ways depending on how you did the install. They are called "EFI" or "BIOS Compatibility". It kind of sounds like you are trying to boot one way at power-up but the machine is configured the other way. I don't have one of these mobo's bit it's something to look into.
See the the posts here , particularly the 3rd one.

It might also be related to EFI "Secure Boot" and possibly a corrupted boot partition.

 

ItsRapidDave

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I'd tried updating the BIOS, made literally no difference at all.
 
Could be the RAM, despite your various arrangements, there may still be more possible configurations you have not tried.

FX CPUs have a poor memory controller that seems to perform adequate with only 2 RAM modules installed.

I've also read that some Gigabyte 990FX boards have a voltage limit of 1.5 V on the memory slots, which if true is annoying and can be very limiting.

On my own Gigabyte 990FX board, the RAM is consistently undervolted to about 1.44, regardless of any custom settings in the BIOS, meaning the RAM can't be made to run stably at anything over 1333 MHz. Choosing to use an XMP profile sometimes gets the board to boot with the 1.65 V I have it configured for, but even this is hardly consistent, and resuming from sleep is never guaranteed.

I would start to troubleshoot your configuration by looking very closely at your memory speed, timings, and most importantly, voltage it's being run at.

You can use CPU-Z to read the SPD information from your RAM modules (when your machine boots) and decide if your RAM is even being configured to run correctly by your BIOS.
 

ItsRapidDave

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I've used Speccy to look at my RAM voltages and according to that they're running at exactly 1.5v. Not sure if that's what they're running at or if that's what they're supposed to run at.
 

ItsRapidDave

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I use two sets, one runs at 669MHz ans the other pair runs at 800MHz, I've looked online and apparently they only show half the frequency, so actually I think the clock speeds are about right.
 
All your RAM runs at the same speed, however timings can be different between channel A and channel B. Your Gigabyte BIOS should allow you that flexibility.

For higher speed or older RAM modules, voltages of over 1.5 V are sometimes required.

You aren't going to be able to set individual voltages for each set of RAM so you will need to set voltage for the RAM modules that require the most voltage at the speed you are running them at, for stability.

Having incorrect timings for your RAM will easily cause you boot up problems. I would look into either setting each RAM pair to their correct timings, respective to their channel, or find a single set of timings for both sets that all of your modules will work correctly with.

Can you list the make and model of RAM modules you have installed, or can you verify the proper operating voltage for your RAM under the SPD information section in Speccy? You want to match the frequency of your RAM to the row in the Frequency column to the Voltage column to see what your RAM module requires to run at that frequency.

Also, verify under the Memory heading that the numbers your memory is running with are the same as the frequency row numbers say they should be, or higher. Higher numbers are generally okay, although not preferred, as this means the memory is being run a bit slower than rated for, but lower numbers indicate the memory is being asked to run faster than it's specified for, and can lead to memory errors (neither is a guarantee.)

You will want to verify the SPD information for each RAM module, since you're using a mixed set of modules.

Also, you want to be certain your RAM module pairs are installed, each pair to it's own channel. You can't just plop any of the four modules you have into any of the four RAM slots on your board. There are two pairs of slots, and you have two pairs of dissimilar RAM. Keep each pair together. Each pair of slots may be right next to each other, or the pairs may alternate slots. The pairs are often color coded, but ultimately, since Gigabyte changes this from one board to the next, you need to read your manual to be certain.

I pulled up the manual for the board you listed in your original post here and at the bottom of page 9 it looks like channel 0 consists of the red and black slots: DDR3_2 & DDR3_4, while channel 1 consists of the red and black slots DDR3_1 & DDR3_3.

What you don't want to do is have each pair of RAM modules occupying the same color slots. One pair should not be in both red, and one pair should not be in both black. According to the board manual, that would be mixing two different RAM modules on each channel. So, for your configuration, you should have one matching RAM module pair closest to the processor, and the other matching RAM module pair in the two slots furthest from the processor.
 

ItsRapidDave

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I didn't realise this was an issue for RAM, but luckily, my RAM is set up properly, they're each on a different channel.

I think it may be easier for me to contact the website I bought the motherboard from and try to get a replacement.
 
Get a replacement what, motherboard? We haven't established there is anything wrong with the motherboard. Replacing the motherboard may end up being a bunch of hassle for zero returns. I would suspect any AM3+ board to behave relatively the same given the mixed RAM situation.

You are running mixed RAM modules. No AMD configuration specifically supports this that I am aware of, however Intel does allow dual-channel, up to a point, under those conditions.

If you fine tune the timings and voltage on your current configuration, you may find it is mostly reliable - Provided there is a set of timings that work.
 
Solution

ItsRapidDave

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But this happens even when I'm only using one set of RAM.