Question Vega 64 bad temp sensor?

[ThEbEsTkiLllLeR]

Hello, I recently bought a Gigabyte RX Vega 64 OC second hand and the dude told me that he used it for a little over a month, so it is nearly new. I paid 240 dollars for it.
Everything works great, I also managed to overclock it quite alot, and it is silent (which surprised me) but the thing is.. the temperature sensor fluctuates alot (it jumps a few degrees for a second and then comes back).
For example I tested it on furmark and it had 65 degrees and then reported 69 degreed just for one second and then going back to 65, and it keeps jumping like this.
Is the temperature sensor damaged or is this normal? Also, what do you guys think of my purchase? (I paid 240$ for the vega 64).
The fan curve works ok, but i wonder what would happen if the temp sensor would break completely...
Also the HBM temperature sensor works just fine (showing constant temperature).

 

[NightAntilli]

What does the fan speed do when you're getting these spikes? Is it constant or does it ramp up and down just like the temperature?

Honestly, the Gigabyte is the worst Vega 56/64 out there, sadly. Many people have issues with them... Hopefully, this will be the biggest issue you have with it... But, if I recall correctly, there is an updated BIOS that fixes a few issues with these cards. Maybe you can look into that..?

 

[ThEbEsTkiLllLeR]

The fan speed is perfectly fine, it ramps up and down just like normal, even though the temps jump a lot. I have no problems with the fans. I heard that it is a bad model but the seller used it for a month with no problems. I also don't have any issues and no crashes at all with it so far, it's been great. Just this temp sensor got me worried a bit, can it break further? Or is the sensor good and I'm worrying too much? I also want to mention that the HBM temp sensor works just fine.
I will post temperature readings from hwinfo shortly. (Also I managed to oc the hbm to 1100mhz and I'm pretty happy )

 

[NightAntilli]

It's hard to tell whether it's good or not. I hope that it isn't honestly, because rapid temperature changes can cause damage to the GPU more easily.

 

[ThEbEsTkiLllLeR]

https://imgur.com/rMPJMTa

View: https://imgur.com/rMPJMTa

You can see that the temperature is going up and down, fluctuating for one second, is it normal? The hbm temps are reported just fine. (I've also set a target temp of 65C in Wattman so that the fans always run at 2200 RPM). Am I worrying too much for nothing? Thanks.
(Also I noticed that there is quite a big difference between the GPU Temp 67-69C and the HBM Temp 82-83C)

 

[NightAntilli]

Well, I don't think those spikes are normal. Do those spikes coincide with the load of the GPU, or is it completely 'random'?

The HBM temperature is normal. You can expect HBM temperature to be between 80 and 85 degrees C.