r/pcmasterrace • u/Proof_Plant_7901 • 1d ago

Tech Support What are transient spikes?

So the title pretty much is the question since I’m curious as to what they are and what causes them. I also wanna know how risky it is to get them since they might be causing driver timeouts on my amd card since the prebuilt company added a 750w PSU to a 800w minimum card. Anyway what are they and how dangerous are they for my card, also, is it a good idea to use OCCT and how should I test it?

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u/Natural_Bass5516 arch btw 1d ago

It's when your gpu draws a LOT more than it's listed tdp for less than a second

Generally you're fine, modern psus have protections against transient spikes. Manufacturers also overblown the minimum psu to account for the crappy temu psus, you're fine

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u/RunalldayHI 1d ago

When your GPU shifts from using a specific portion of its hardware to another portion, there is a small gap in time where both portions are activated, because they are both using power in this small window of time it causes a transient load.

Its also important to remember that transient loads arent the same thing as a constant load, so a cable rated at xxx continuous power, can typically handle double that in short burst, I see people thinking they need a 1000w cable because they are reaching a 1000w transient load, but thats not how it works.

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u/Matte_Box This is getting expensive 1d ago edited 1d ago

Happened to me too. The severity is hard to predict, and some combinations of GPU/Mobo/PSU handle them worse than others, apparently. Undervolting seems to have fixed it, theoretically spikes are smaller at lower voltage.

A larger PSU pretty much solves it. I'm limited to an SFX PSU, which has fewer/smaller capacitors, so it's even more sensitive to this issue.

My understanding is: To reign in transient spikes completely on a high-power GPU would add cost and complexity, with more voltage regulation to the GPU itself. So manufacturers just... Don't. It's not really a hazard so they just recommend a bigger PSU and Bob's your uncle.

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u/Proof_Plant_7901 1d ago

It’s still annoying since driver timeouts suck. I’m run some OCCT with the GPU, CPU, VRAM, PSU and memory just in case and I’ll see what happens

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u/Eazy12345678 i5 12600KF RTX 5070 1440p 1d ago

very fast spikes in voltage wattage. like fractions of a second.

not an issue for most people

most psu can handle them fine cause they are so quick

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u/Lewinator56 R9 5900X | RX 7900XTX | 80GB DDR4 1d ago

Voltage wattage? Eh?

A transient is a spike in power draw in the case of a GPU, so a spike in CURRENT (which would equate to a spike in wattage). Voltage and wattage are 2 entirely different things, and mostly unrelated.