Limitations of my CPU for 4k gaming

Blueyoshi03 · 2025-01-15T15:06:11+0000

I have been running a 9700K at all core 4.9ghz for many years now with a 1080ti and has been running well for this time. I am running this on a 3440x1440 monitor at a max 120hz which is usually not achievable with the 1080ti in most modern titles.

I will be purchasing a 5080 on release which will be a huge graphics upgrade and don't see any current benefit to upgrading the CPU and ram at the moment, however I had a question to understand my CPU performance.

If I understand everything right, to measure my CPU as a bottleneck, if I can run a game at low resolution at 120fps+, would this nearly always mean the system can run any resolution at that fps as long as there is not a gpu bottleneck?

I want to know when it would actually make a difference to upgrade my cpu

Toasty · 2025-01-15T15:32:22+0000

Yeah pretty much if your CPU can generate 120+ FPS at low resolution, then when you remove the GPU as a bottleneck then you should be good to increase resolution.

You would need to test in all the games important to you though as they will have very different demands on the CPU depending on engine and things like NPC A.I. Can't just do one game and say its ok for all.

Also DLSS/RT could also influence the results but 120fps is not really an insane ask for a modern cpu.

mpj88 · 2025-01-15T15:35:42+0000

Blueyoshi03 said:
I have been running a 9700K at all core 4.9ghz for many years now with a 1080ti and has been running well for this time. I am running this on a 3440x1440 monitor at a max 120hz which is usually not achievable with the 1080ti in most modern titles.

I will be purchasing a 5080 on release which will be a huge graphics upgrade and don't see any current benefit to upgrading the CPU and ram at the moment, however I had a question to understand my CPU performance.

If I understand everything right, to measure my CPU as a bottleneck, if I can run a game at low resolution at 120fps+, would this nearly always mean the system can run any resolution at that fps as long as there is not a gpu bottleneck?

I want to know when it would actually make a difference to upgrade my cpu

You can check your GPU/CPU utilization when you upgrade, this will give indication on how much of a bottleneck your CPU is. I'm hitting CPU limitations currently

SpellowHouse · 2025-01-15T15:41:04+0000

I think the biggest issue with the 9700K may well be your 1% lows. But whatever, just get the 5080 and see what it's like. If you are getting unexpected low performance you know where the problem is!

Blueyoshi03 · 2025-01-15T15:42:08+0000

Ah OK that's interesting, are the 1% lows the responsibility or at least part responsibility of a CPU?

SpellowHouse said:
I think the biggest issue with the 9700K may well be your 1% lows. But whatever, just get the 5080 and see what it's like. If you are getting unexpected low performance you know where the problem is!

Disco_P · 2025-01-15T15:44:08+0000

Blueyoshi03 said:
Ah OK that's interesting, are the 1% lows the responsibility or at least part responsibility of a CPU?

Usually yes (though it can also be drivers or the game and there isn't a lot you can do about those)

Toasty · 2025-01-15T16:03:11+0000

1% lows latency dependent CPU/RAM driver overhead.

9th and 10th gen were/are pretty damn good and responded well to tuning. Could look at your ram and your uncore to increase performance depending on where it sits right now.

Bidley · 2025-01-15T19:48:31+0000

Depends what games you play, it's not a one-size-fits-all. More and more modern games are pushing your CPU harder. My 3080 was bottlenecked by a 5700x in CPU-demanding scenarios.

I used PresentMon frametime compared to CPU/GPU busy times. It's included in hwinfo.

Rroff · 2025-01-15T20:06:57+0000

If you are happy with the performance at 1080p then as long as the GPU isn't a bottleneck you should still get good performance at 4K however some newer games will benefit from having more than 8 threads available, the 9700K will definitely bottleneck stuff like the 5080 from its best performance at 4K and in some cases quite considerably these days - you are probably leaving 1/3rd or so of the performance of the GPU on the table even at 4K and probably not gaining much over a 3080 or so.

Sone · 2025-01-15T21:12:17+0000

I had a 5900x went to 9800x3d. Saw zero difference. Before the 5900x had a 4930k saw zero difference. Personally at 4K i think the 9700k will do fine with 5080.

Rroff · 2025-01-15T21:17:01+0000

Sone said:
I had a 5900x went to 9800x3d. Saw zero difference. Before the 5900x had a 4930k saw zero difference. Personally at 4K i think the 9700k will do fine with 5080.

With what GPU?

I have a Xeon 1650 V2 which is essentially the same as the 4930K and anything beyond approx. a 3070 it is a bottleneck - the difference compared with my 14700K on the 4080 Super even at 4K is pretty big.

Sone · 2025-01-15T21:19:31+0000

Complicat

Rroff said:
With what GPU?

Slightly complicated.. Had a 1080ti 4930k -> 5900x. Upgraded to a 3090. Then got a 4080super with the 9800x3d (got a second hand machine price i could not refuse). But from 5900x + 3090 to 9800x3d + 4080 super there is naff all difference

Rroff · 2025-01-15T21:22:39+0000

Sone said:
Complicat

Slightly complicated.. Had a 1080ti 4930k -> 5900x. Upgraded to a 3090. Then got a 4080super with the 9800x3d (got a second hand machine price i could not refuse). But from 5900x + 3090 to 9800x3d + 4080 super there is naff all difference

5900X at 4K with a 4080 Super will still hold up pretty well, some 1% lows, etc. difference but average performance against the 7000/9000 X3D chips won't be much different (despite the impression people get due to all the 1080p benchmarks), be a different story if you put the 4930K back in though :s

Sone · 2025-01-15T21:26:34+0000

Rroff said:
5900X at 4K with a 4080 Super will still hold up pretty well, some 1% lows, etc. difference but average performance against the 7000/9000 X3D chips won't be much different (despite the impression people get due to all the 1080p benchmarks), be a different story if you put the 4930K back in though :s

4930k machine bit the dust. Do have a 5960X still hanging around. Perhaps i should give it ago

silvagti · 2025-01-15T21:27:31+0000

I was planning on buying a new 27" 4K 240Hz OLED and pairing it with a Ryzen 7 9700X / Geforce RTX 5070Ti (or RTX 5080) when the new GPUs and monitors release. I was intending on using it primarily for space sims like Elite Dangerous / Star Citizen and playing VR titles using my Meta QUest 3 headset.

Is that a bad move as I assumed for 4K or VR gaming that the CPU wouldn't really be a bottleneck unless you're aiming for super high 120 FPS+ framerates in FPS games?

Rroff · 2025-01-15T21:31:05+0000

Sone said:
4930k machine bit the dust. Do have a 5960X still hanging around. Perhaps i should give it ago

I've still got my Xeon 1650 V2 which is basically the same chip as the 4930K - with my 4080 Super the difference to the 14700K (or 7800X3D) is massive even at 4K heh.

Though those X79 V2 systems hold up way better than people think when you've got a good overclock and some decent RAM on them - far too many of the reviews of them use stock loose timing 1600MHz RAM which doesn't show them at their best.

Sone · 2025-01-15T21:38:12+0000

Rroff said:
I've still got my Xeon 1650 V2 which is basically the same chip as the 4930K - with my 4080 Super the difference to the 14700K (or 7800X3D) is massive even at 4K heh.

Though those X79 V2 systems hold up way better than people think when you've got a good overclock and some decent RAM on them - far too many of the reviews of them use stock loose timing 1600MHz RAM which doesn't show them at their best.

Do love an old Xeon, price to performance unbeatable, and if buy as a system usually comes with decent PSU etc. Have a few E5-2690 and a Dual 2699v3 system still in use.

Quartz · 2025-01-15T21:44:43+0000

Blueyoshi03 said:
Ah OK that's interesting, are the 1% lows the responsibility or at least part responsibility of a CPU?

There are two major causes of 1% lows: the CPU and texture paging from a lack of VRAM. The latter should not affect you with a 5080.

Tythus · 2025-01-15T22:10:01+0000

Blueyoshi03 said:
I have been running a 9700K at all core 4.9ghz for many years now with a 1080ti and has been running well for this time. I am running this on a 3440x1440 monitor at a max 120hz which is usually not achievable with the 1080ti in most modern titles.

I will be purchasing a 5080 on release which will be a huge graphics upgrade and don't see any current benefit to upgrading the CPU and ram at the moment, however I had a question to understand my CPU performance.

If I understand everything right, to measure my CPU as a bottleneck, if I can run a game at low resolution at 120fps+, would this nearly always mean the system can run any resolution at that fps as long as there is not a gpu bottleneck?

I want to know when it would actually make a difference to upgrade my cpu

Only thing which might make you want to update is the lack of resizeable bar support I think that came in on 10th gen intel so you would be leaving performance on the table and it's pcie gen 3 x16 I think not that I think you'll lose much but you never know

Capitano · 2025-01-15T22:20:25+0000

better cpu and your 1% lows will improve while it may not make too much of a difference for average fps in 4k gaming