Question Suspect RAM issue, need help.

dunlapc308

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Dec 9, 2012
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I built a new system a few weeks ago and have been slowly fighting with it, trying to figure out some issues I think are for to RAM. It's my first Ryzen build and I've read that Ryzen is fairly tied to the memory accompanying it. System specs below.

CPU: Ryzen 7 3700x
Memory: G.Skill Trident Z RGB 3600mhz (2x16GB)
Mobo: Gigabyte x570 Aorus Elite
GPU: ASRock Challenger RX 5700 XT
Case: Corsair 275R w/ 6 AF120 case fans

I started noticing issues when I would play steam games. Some of the not demanding games will occasionally just close without any warning or error messages.

I have XMP enabled on my RAM. After doing some research, I decided to run memtest, though I should have done that from the beginning. Memtest passed all tests with no errors with RAM clocked at 3600mhz. So then I booted up the machine and ran Prime95 blend test. Several threads fail with the following (or similar) error almost immediately.

Fatal error: rounding was .5, expected less than .4

The longer I let it run, the more threads fail. I then ran a short Prime95 Small FFT and Medium FFT test and didn't see any issues. When running the Large FFT test, I see the errors but it takes longer than in a blend test.

I tried bumping XMP settings down to 3466 instead of 3600, with no change in results.

I thought it might be thermals related, but during these tests, the CPU isn't getting over 65c. I don't have temps on the memory but I have a hard time believing the memory should have thermal issues if the CPU and GPU are running fine.

I'm honestly not sure what other things I should be looking at, other tests I should run, or if this is indicative of a CPU issue or a RAM issue. What I've seen makes me think it's a RAM issue. Is this an issue with RAM thermals? Does that mean the RAM is bad and I should RMA it or should I be do something else to improve cooling?
 
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dunlapc308

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Thanks Nemesia for the link. After reading through that, I decided to try setting the CPU voltage manually in BIOS (it was set to Auto before). I set it to 1.3v and then 1.35v but still am seeing the same results in the prime95 blend test. What I'm confused about is that during the test, Ryzen Master is showing a peak core voltage of 0.98, clocks are running around 2200ghz on each core and CPU temp is at 66c. Does this mean the CPU is being throttled because of temp?
 

dunlapc308

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Just to cover the bases I decided to disabled XMP completely and run the test again. Prime95 blend test has been running for 2 hours now with no errors.

I know that XMPs are not always achievable but considering the RAM was rated for 3600 and advertized as optimized for Ryzen and I haven't been able to get it stable at even 3466, do these results mean my RAM is faulty or is there something else I could try?
 

Phaaze88

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The thing is, the XMP profiles are for Intel cpus. They may, or may not work well with Ryzen cpus.
The timings used in this profile are likely not agreeing with your 3700X.

Look up Ryzen Dram Calculator. With that, you should be able to configure a set of timings that will allow your 3700X to run with 3600mhz.
 

dunlapc308

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I feel like an idiot. As I was adjusting some settings in BIOS I noticed that even though the date the bios was updated was the same as the most recent version listed on Gigabytes website, it was not the same version. My mobo was running version F4 of the BIOS, they were on version F11. Updated BIOS and everything seems to be running completely stable even at the 3600mhz XMP profile defaults. And my temps are lower, so that's a nice plus.

Thanks for the help. I actually had already downloaded the DRAM calculator. Cool tool but was trying to make tweaks elsewhere before I jumped off the deep end. I'll be looking at that in the future though as I explore some potential OCs.

Thanks everyone!
 
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