CPU Power Consumption Questions

[pavichokche]

I'm designing a new PC build and I want it to be power-conscious. To that effect, I want to make sure I have a proper understanding first. Here are my two main questions, I'll keep them general:

1. Would a more powerful CPU (i7 vs i5) use more power under the same idle conditions?
2. Would a more powerful CPU (i7 vs i5) use more power to keep the same game running at 60fps?

This article has been a good read on the topic. If nothing else, it's a clear indicator that the TDP of an Intel CPU is definitely not close to its actual maximum power draw.

Ideally, I would like to upgrade to an i7 (probably 7700) so that my PC runs a bit faster and I can optimize some CPU-hungry games. However, I'm worried it would use more power than an i5 (probably 7600) while just idling, or when being under-utilized by a v-synced game.

 

[jdcranke07]

I'm designing a new PC build and I want it to be power-conscious. To that effect, I want to make sure I have a proper understanding first. Here are my two main questions, I'll keep them general:

1. Would a more powerful CPU (i7 vs i5) use more power under the same idle conditions?
2. Would a more powerful CPU (i7 vs i5) use more power to keep the same game running at 60fps?

This article has been a good read on the topic. If nothing else, it's a clear indicator that the TDP of an Intel CPU is definitely not close to its actual maximum power draw.

Ideally, I would like to upgrade to an i7 (probably 7700) so that my PC runs a bit faster and I can optimize some CPU-hungry games. However, I'm worried it would use more power than an i5 (probably 7600) while just idling, or when being under-utilized by a v-synced game.

You are correct that the TDP rating by Intel is not the max consumption of any of their chips. It is what the chip should be around at stock settings for clock speeds, but with turbo clocks or overclocking they can easily hit over the TDP wattage in their spec sheets. TDP ratings are mainly gearing you to pick out the type of cooling that you will need for the CPU more than the actual power consumption of the chip.

As far as the i7 vs the i5 chips, both will idle very low and will utilize power saving features that will drop the amount of consumption greatly, however they will both ramp up whenever there is a process that needs to be completed and if you use background applications, then your CPU might only idle for a bit and then ramp up and ramp down in spurts when a process comes up. But, in any case, the CPU will not be the biggest reason for power draining performance, compared to other components, and if you don't build a PC that is super tight on wattage delivered from the PSU and actually give yourself some head room, you won't have to worry about power consumption. Also, a PSU will only deliver as much power as is required by the parts and will not pull their full rating from the wall unless you make the PC as a whole run that heavy of a load. I.e. my EVGA SuperNOVA 1600 T2 will not draw 1600W at all unless I ramp all of my components up to maximum consumption.

Getting back to the i7 vs i5. An i7 has the ability to pull more power than an i5 because it can do way more. The 7700K, having 8 threads can indeed and easily pull more wattage than the 7600K, but the 7700K wouldn't pull much more, if any, at idle speeds vs the 7600K at idle. Your main concern on wattage consumption should be directed to your GPU in my opinion since it can easily pull more wattage than your CPU could.

 

[pavichokche]

I'm designing a new PC build and I want it to be power-conscious. To that effect, I want to make sure I have a proper understanding first. Here are my two main questions, I'll keep them general:

1. Would a more powerful CPU (i7 vs i5) use more power under the same idle conditions?
2. Would a more powerful CPU (i7 vs i5) use more power to keep the same game running at 60fps?

This article has been a good read on the topic. If nothing else, it's a clear indicator that the TDP of an Intel CPU is definitely not close to its actual maximum power draw.

Ideally, I would like to upgrade to an i7 (probably 7700) so that my PC runs a bit faster and I can optimize some CPU-hungry games. However, I'm worried it would use more power than an i5 (probably 7600) while just idling, or when being under-utilized by a v-synced game.

You are correct that the TDP rating by Intel is not the max consumption of any of their chips. It is what the chip should be around at stock settings for clock speeds, but with turbo clocks or overclocking they can easily hit over the TDP wattage in their spec sheets. TDP ratings are mainly gearing you to pick out the type of cooling that you will need for the CPU more than the actual power consumption of the chip.

As far as the i7 vs the i5 chips, both will idle very low and will utilize power saving features that will drop the amount of consumption greatly, however they will both ramp up whenever there is a process that needs to be completed and if you use background applications, then your CPU might only idle for a bit and then ramp up and ramp down in spurts when a process comes up. But, in any case, the CPU will not be the biggest reason for power draining performance, compared to other components, and if you don't build a PC that is super tight on wattage delivered from the PSU and actually give yourself some head room, you won't have to worry about power consumption. Also, a PSU will only deliver as much power as is required by the parts and will not pull their full rating from the wall unless you make the PC as a whole run that heavy of a load. I.e. my EVGA SuperNOVA 1600 T2 will not draw 1600W at all unless I ramp all of my components up to maximum consumption.

Getting back to the i7 vs i5. An i7 has the ability to pull more power than an i5 because it can do way more. The 7700K, having 8 threads can indeed and easily pull more wattage than the 7600K, but the 7700K wouldn't pull much more, if any, at idle speeds vs the 7600K at idle. Your main concern on wattage consumption should be directed to your GPU in my opinion since it can easily pull more wattage than your CPU could.

Thank you for your answer! I will feel more at ease about getting that i7 processor now. I have a 500W PSU I believe, and it's GOLD rated. My GPU is a GTX1060 by Gigabyte. I keep all my games v-synced at 60fps, so with the correct settings I can keep my GPU at a pretty low voltage. While gaming my current system sips 110-160W (out of the wall) depending on my GPU's activity, usually around 130. That tends to keep my GPU fanless most of the time too.

 

[jdcranke07]

I'm designing a new PC build and I want it to be power-conscious. To that effect, I want to make sure I have a proper understanding first. Here are my two main questions, I'll keep them general:

1. Would a more powerful CPU (i7 vs i5) use more power under the same idle conditions?
2. Would a more powerful CPU (i7 vs i5) use more power to keep the same game running at 60fps?

This article has been a good read on the topic. If nothing else, it's a clear indicator that the TDP of an Intel CPU is definitely not close to its actual maximum power draw.

Ideally, I would like to upgrade to an i7 (probably 7700) so that my PC runs a bit faster and I can optimize some CPU-hungry games. However, I'm worried it would use more power than an i5 (probably 7600) while just idling, or when being under-utilized by a v-synced game.

You are correct that the TDP rating by Intel is not the max consumption of any of their chips. It is what the chip should be around at stock settings for clock speeds, but with turbo clocks or overclocking they can easily hit over the TDP wattage in their spec sheets. TDP ratings are mainly gearing you to pick out the type of cooling that you will need for the CPU more than the actual power consumption of the chip.

As far as the i7 vs the i5 chips, both will idle very low and will utilize power saving features that will drop the amount of consumption greatly, however they will both ramp up whenever there is a process that needs to be completed and if you use background applications, then your CPU might only idle for a bit and then ramp up and ramp down in spurts when a process comes up. But, in any case, the CPU will not be the biggest reason for power draining performance, compared to other components, and if you don't build a PC that is super tight on wattage delivered from the PSU and actually give yourself some head room, you won't have to worry about power consumption. Also, a PSU will only deliver as much power as is required by the parts and will not pull their full rating from the wall unless you make the PC as a whole run that heavy of a load. I.e. my EVGA SuperNOVA 1600 T2 will not draw 1600W at all unless I ramp all of my components up to maximum consumption.

Getting back to the i7 vs i5. An i7 has the ability to pull more power than an i5 because it can do way more. The 7700K, having 8 threads can indeed and easily pull more wattage than the 7600K, but the 7700K wouldn't pull much more, if any, at idle speeds vs the 7600K at idle. Your main concern on wattage consumption should be directed to your GPU in my opinion since it can easily pull more wattage than your CPU could.

Thank you for your answer! I will feel more at ease about getting that i7 processor now. I have a 500W PSU I believe, and it's GOLD rated. My GPU is a GTX1060 by Gigabyte. I keep all my games v-synced at 60fps, so with the correct settings I can keep my GPU at a pretty low voltage. While gaming my current system sips 110-160W (out of the wall) depending on my GPU's activity, usually around 130. That tends to keep my GPU fanless most of the time too.

If you plan to turn your PC off when you are not using it, then that PSU rating will be more than fine. If you plan to have it on 24/7, having a higher 80+ rating might be worth the power savings it can offer. Other than that, you're good.