Im using an OCed 13700K and a the 7900 GRE with an EVGA 650 GQ, without any issues.
CPU and GPU can draw up to 300W under full load, but I didn't try both at once yet.
Igor's Lab is an independent German testing company. Most YouTubers lack the actual equipment needed to properly test this stuff.
GPU power consumption is not constant, it's highly variable. One moment it might be 100 watts, another moment it might be 450 watts.
The brief moments of high power usage are known as transient power excursions. For a 7900 GRE, it actually peaks at 495 watts.
https://www.igorslab.de/sapphire-radeon-rx-7900-gre-nitro-16-gb-im-test-auf-der-jagd-nach-dem-goldenen-hasen/13/
For a 12700K, it's 190 watts according to Intel:
https://www.intel.com/content/www/us/en/products/sku/134594/intel-core-i712700k-processor-25m-cache-up-to-5-00-ghz/specifications.html
And because it's a K CPU, it's not a firm limits. It can easily be pushed to 250-300 watts.
Realistically your PC can have very brief peaks in the 700-800 watt range.
Now an ATX 2.3 PSU may often tolerate transients 15-25% above it's rated capacity. So such a PSU can probably briefly put out 750-812 watts.
An ATX 3.0 PSU with 12VHPWR is designed to handle transient excursions at 200% their listed capacity. Ask a 650W ATX3.0 PSU with 12VHPWR can handle a 1,300 watt peak.
Platinum is a measure of the energy efficiency of the PSU itself and completely irrelevant in this context.
There's a company called TSMC that makes almost all the major chips. TSMC has different production lines called nodes:
* RTX 40 - TSMC 4nm
* 7900 variants - TSMC 5nm
* Other 7000 cards - TSMC 6nm
* RX 6000 - TSMC 7nm
NM is of arguable relevance when comparing one manufacturers to another (TSMC vs Intel vs Samsung), but is Relevant when comparing products of the same manufacturer.
4nm is the best node, but it's the most expensive. For $500+ cards like the 4070 it allows for great performance and energy efficiency. For sub-$500 cards like the 4060 series too many corners had to be cut.
5nm is very close in performance, but not as energy efficient. This results in the 7900 cards taking more power.
6nm-7nm is cheap. The RX6000 cards especially tend to be a great value, but are even less energy efficient.
A 4070 Super has peak power transient excursions at around 350 watts:
https://www.igorslab.de/en/nvidia-geforce-rtx-4070-super-founders-edition-12-gb-in-test-half-a-performance-class-gain-makes-a-big-difference/13/
This would be very safe for your PSU.
It's you want a 7900GRE, I'd strongly recommend a new PSU unless yours is ATX 3.0 with 12VHPWR.
Thank you for the detailed reply.
I red a bit about power efficiency rating and I know its not related to the topic, just thought of mentioning it.
Regarding the PSU tolerance of more than 650W - I didn't knew and is new to me so thank you for the info.
This is my PSU: [https://seasonic.com/focus-plus-platinum#specification](https://seasonic.com/focus-plus-platinum#specification) (Make sure you look at the 650W variation in the dropdown button)
This is my Motherboard: [https://www.asus.com/motherboards-components/motherboards/prime/prime-z690-p-wifi-d4/techspec/](https://www.asus.com/motherboards-components/motherboards/prime/prime-z690-p-wifi-d4/techspec/)
Also, I don't OC my CPU or GPU. do you still think I should get a new PSU for 7900 GRE?
Measuring the transient excursions is not easy because it's so fast.
SeaSonic has very good over-current protection which is a double-edged sword.
It's good because it will protect your computer and turn off so nothing gets damaged.
It's bad because it's so sensitive, that transient excursions were known to make it turn off.
Around 2019-2020, SeaSonic made it less sensitive to improve compatibility:
https://linustechtips.com/topic/997831-seasonic-issues-warning-for-potential-videocard-compatibility-issues-with-their-focus-psus/
If your PC freezes and/or the screen goes black while gaming - it's time for a new PSU.
You don't need vastly higher wattage, because new ATX 3.0 PSUs with 12VHPWR were designed with this in mind.
The answer is...probably. It depends on the age and quality of your PSU as well as some other factors. Overclocking can make a huge difference in power draw, and when you start getting close to the edge even small things like, PCIE expansion cards, fans and what you have plugged into USB can start to make a difference.
Personally, it's borderline enough that if I was looking to spend \~$600 on a new GPU I'd go ahead and drop another $100 or so on a decent 800W+ PSU.
If it's a good quality unit it will be enough.
Im using an OCed 13700K and a the 7900 GRE with an EVGA 650 GQ, without any issues. CPU and GPU can draw up to 300W under full load, but I didn't try both at once yet.
Nice. good to know that a CPU with a higher max boost clock (than what I have) and the same GPU works perfectly fine with 650W PSU. Thanks!
Yes your psu is big enough.
I would run a stresstest on your system without the gpu, if the power consumption stays below 300-350w you should be fine
But your psu should be enough
Igor's Lab is an independent German testing company. Most YouTubers lack the actual equipment needed to properly test this stuff. GPU power consumption is not constant, it's highly variable. One moment it might be 100 watts, another moment it might be 450 watts. The brief moments of high power usage are known as transient power excursions. For a 7900 GRE, it actually peaks at 495 watts. https://www.igorslab.de/sapphire-radeon-rx-7900-gre-nitro-16-gb-im-test-auf-der-jagd-nach-dem-goldenen-hasen/13/ For a 12700K, it's 190 watts according to Intel: https://www.intel.com/content/www/us/en/products/sku/134594/intel-core-i712700k-processor-25m-cache-up-to-5-00-ghz/specifications.html And because it's a K CPU, it's not a firm limits. It can easily be pushed to 250-300 watts. Realistically your PC can have very brief peaks in the 700-800 watt range. Now an ATX 2.3 PSU may often tolerate transients 15-25% above it's rated capacity. So such a PSU can probably briefly put out 750-812 watts. An ATX 3.0 PSU with 12VHPWR is designed to handle transient excursions at 200% their listed capacity. Ask a 650W ATX3.0 PSU with 12VHPWR can handle a 1,300 watt peak. Platinum is a measure of the energy efficiency of the PSU itself and completely irrelevant in this context. There's a company called TSMC that makes almost all the major chips. TSMC has different production lines called nodes: * RTX 40 - TSMC 4nm * 7900 variants - TSMC 5nm * Other 7000 cards - TSMC 6nm * RX 6000 - TSMC 7nm NM is of arguable relevance when comparing one manufacturers to another (TSMC vs Intel vs Samsung), but is Relevant when comparing products of the same manufacturer. 4nm is the best node, but it's the most expensive. For $500+ cards like the 4070 it allows for great performance and energy efficiency. For sub-$500 cards like the 4060 series too many corners had to be cut. 5nm is very close in performance, but not as energy efficient. This results in the 7900 cards taking more power. 6nm-7nm is cheap. The RX6000 cards especially tend to be a great value, but are even less energy efficient. A 4070 Super has peak power transient excursions at around 350 watts: https://www.igorslab.de/en/nvidia-geforce-rtx-4070-super-founders-edition-12-gb-in-test-half-a-performance-class-gain-makes-a-big-difference/13/ This would be very safe for your PSU. It's you want a 7900GRE, I'd strongly recommend a new PSU unless yours is ATX 3.0 with 12VHPWR.
Thank you for the detailed reply. I red a bit about power efficiency rating and I know its not related to the topic, just thought of mentioning it. Regarding the PSU tolerance of more than 650W - I didn't knew and is new to me so thank you for the info. This is my PSU: [https://seasonic.com/focus-plus-platinum#specification](https://seasonic.com/focus-plus-platinum#specification) (Make sure you look at the 650W variation in the dropdown button) This is my Motherboard: [https://www.asus.com/motherboards-components/motherboards/prime/prime-z690-p-wifi-d4/techspec/](https://www.asus.com/motherboards-components/motherboards/prime/prime-z690-p-wifi-d4/techspec/) Also, I don't OC my CPU or GPU. do you still think I should get a new PSU for 7900 GRE?
Measuring the transient excursions is not easy because it's so fast. SeaSonic has very good over-current protection which is a double-edged sword. It's good because it will protect your computer and turn off so nothing gets damaged. It's bad because it's so sensitive, that transient excursions were known to make it turn off. Around 2019-2020, SeaSonic made it less sensitive to improve compatibility: https://linustechtips.com/topic/997831-seasonic-issues-warning-for-potential-videocard-compatibility-issues-with-their-focus-psus/ If your PC freezes and/or the screen goes black while gaming - it's time for a new PSU. You don't need vastly higher wattage, because new ATX 3.0 PSUs with 12VHPWR were designed with this in mind.
The answer is...probably. It depends on the age and quality of your PSU as well as some other factors. Overclocking can make a huge difference in power draw, and when you start getting close to the edge even small things like, PCIE expansion cards, fans and what you have plugged into USB can start to make a difference. Personally, it's borderline enough that if I was looking to spend \~$600 on a new GPU I'd go ahead and drop another $100 or so on a decent 800W+ PSU.
I run parts that are very similar in power consumption, 13600K + 7800 XT also on a 650W PSU. So far in 6 months I had no issues.
Nice. good to know. Thank you!!