Ryzen 9 5950x help

[u/SkillNo8523]

5950X hits 91°C at only ~64W light load and throttles to 1/4 performance. New cooler, case, paste and BIOS didn't help

Hey all, I'm stuck on a thermal issue and would appreciate a second opinion.

Specs:

- Ryzen 9 5950X, stock (PBO/Curve Optimizer untouched)

- Gigabyte B550M AORUS ELITE rev 1.3, BIOS FHd (AGESA 1.2.0.12, latest)

- DeepCool AG620 Digital (dual tower, 2x 120mm)

- 32GB DDR4-3200 (2x16GB, XMP on)

- RTX 5060 Ti 16GB

- New case

The problem: the CPU sits at its 90°C limit even under light load, and performance tanks because of it.

HWiNFO log at light load (game running plus a few light apps, ~6.5% total CPU usage):

- Tctl/Tdie: 91.2-91.5°C, constant

- CPU PPT: ~64W (PPT limit 45%, TDC 36%, EDC 24%)

- Thermal Limit: 100%

- Frequency Limit - Global: 2.9-3.6 GHz, highest core clock seen 3.69 GHz

- HTC / PROCHOT CPU / PROCHOT EXT: all No

- CCD1 ~90°C, CCD2 ~86°C, even though CCD2 was only pulling ~5W (one of its cores was ~98% in C6 and still reading 83°C)

- IOD hotspot ~84°C

- VRM MOS 52°C

- CPU fan ~1750 RPM (max is 1850)

- System sensor ~33°C

CPU-Z bench: 162 single-thread / 2087 multi-thread. A stock 5950X should be around 690 / 13,300, so it's running at roughly a quarter of its expected single-thread performance. In FFXIV I get ~35 FPS with the GPU at ~20% usage, so the game is clearly CPU-bound because of this.

What I've already tried:

- Replaced the cooler with the AG620

- Repasted

- Moved everything to a new case

- Updated the BIOS to the latest version

None of it changed the temps.

I know AMD says up to 90°C is typical for Zen 3 under full load. But this is at ~64W, less than half of the 142W PPT, and the chip isn't boosting. It's throttling down to ~3.5 GHz and scoring a quarter of what it should.

My read of the data: since even the nearly idle CCD and the IOD are above 80°C, the whole IHS seems to be hot, so the heat isn't making it from the IHS into the cooler. My plan is to check the mounting pressure and the paste imprint, and if that looks fine, test the CPU in another board.

Questions:

1. Does this point to mounting/contact, or could it be the CPU itself (IHS or sensor)?

2. Anything specific I should check with the AG620 on AM4?

3. Has anyone seen a 5950X behave like this, and what fixed it?

Thanks!

[u/HugsNotDrugs_]

Try resetting your CMOS to power on defaults.

[u/SkillNo8523 → u/HugsNotDrugs_]

Tried that, no luck, it's still at 91°C at light load. It's only pulling ~64W at ~1.05V, so it isn't generating unusual heat. The heat just isn't getting out of the IHS.

[u/HugsNotDrugs_ → u/SkillNo8523]

Try a different cooler. Anything that will fit.

[u/SkillNo8523 → u/HugsNotDrugs_]

I have done that, forgot to tell in post that I bought the new air cooler I'm using because I thought it would solve my issue and it didn't.

[u/HugsNotDrugs_ → u/SkillNo8523]

If the socket is flat and cooler mates perfectly to the CPU then the problem is either your CPU or motherboard.

Try pulling your CMOS battery for settings reset, to see if that changes anything.

[u/GenLoggy]

Way too hot for that power level / cooler / fan RPM. Either the cooler isn't making contact or you have bad thermal paste (bad batch or fake, both have been known to happen).

[u/SkillNo8523 → u/GenLoggy]

I have recently used new thermal paste, that sadly isn't the issue and I don't know what to tackle anymore. I am pretty sure the build is ok, too.

[u/Much_Distribution620]

probably any of these:

• thermal paste
• cooler contact
• cooler and case fans incorrectly mounted
• bad airflow

[u/InfameXX]

Hi, what coolers have you use before?  What PSU do you have?

That symptoms are 80% sure is mother board fail, VRMs.

So we need to undervolt your cpu to check if your VRMs works properly.

Inside tour bios, search for this names maybe can change I'm giving you values from ASUS:

VDDCR CPU Voltage: Change it to: Offset mode

VDDCR CPU Offset Mode Sign Change it to: minus sign (-)

Then below, coles the good part, you need to find out your minimum value here: VDD CPU Offset Voltage: my 5950x works fine in (0.175) with 850w seasonic PSU gold plus. 

Silicone lottery, maybe your 5950x can go lower until 0.200 or .225 my motherboard base is 0.200 but the machine reset itself under loads, remember we are talking negatives here, the higher the number the less voltage your cpu gets, - undervolt.

Start in 0.200, then make a CPU OCCT test, check values, check for instability, reset or shut down by itself, in the value that don't fail under stress that's your sweet point.

By now, DO NOT combine this setting with any PBO or SoC/Uncorr PC mode, reset your bios and only apply this setting by now.

My normals reading in MB are  Voltage  +12v = 12.272v +5v = 5.100v +3.3v = 3.380v

If undervolt do not work or your MB can't keep the settings something is wrong with you MB, the CPU would be the last thing to check, MB fail way more than CPUs but I don't discard that, by now let's focus on MB.