Bang for buck: CPU or GPU upgrade?

[X-31_VECTOR]

As I've gotten more into VR recently, and placed a preorder for the HP Reverb G2 (to replace my Rift CV1), and I know my current rig will be challenged by the higher resolution. I've got an 17-6700K at 4.3 Ghz, and a GTX1080 (not Ti). Memory is 32GB.

 

I'd resigned myself to replacing the 1080 when the 3080 comes out, as more resolution usually means needing more GPU. But this being VR, I'm wondering how likely I am to see diminishing returns due to CPU bottleneck. Am I damned to replacing both? At this point a new CPU means a new mobo too... thus begins the budget death-spiral.

[Taz1004]

GPU upgrade and overclock CPU.

[SneakyBastd]

Friend of mine and I have been comparing benchmark results in DCS with our similar, but different systems. He has 6600K@4.6, 32GB DDR3 with 2080Ti. I have 7700K@5.1 32GB DDR4 3600 with 1080Ti. We both have Pimax 5k+.

 

I generally beat him in FPS, as it mostly comes down to CPU. However, he can afford to push supersampling and MSAA, while I can afford neither.

So don't expect a new GPU to give you lots of extra FPS, but it seems it can certainly help with attaining higher resolutions and image quality.

For example, we both normally run normal FoV (medium), but when we go to maximum FoV, he loses only half the FPS that I do.

 

So a better GPU helps at high res, but you need a good cpu to stand a chance at realising those frames in the first place. See how hard you can overclock that 6700k!

[Merlin_VFA34]

Hi,

 

 

I have a Reverb G1, 7700K@4.7GHz ,a 2080TI, 32GB RAM and two SSDs Raid0 solely for DCS. According to VRFPS the frametimes of the CPU are about 22ms and the frametimes of the GPU 12ms so I guess your future system would also have a cpu bottleneck.

 

 

Greetings

Merlin :huh:

[eaglecash867]

As I've gotten more into VR recently, and placed a preorder for the HP Reverb G2 (to replace my Rift CV1), and I know my current rig will be challenged by the higher resolution. I've got an 17-6700K at 4.3 Ghz, and a GTX1080 (not Ti). Memory is 32GB.

 

I'd resigned myself to replacing the 1080 when the 3080 comes out, as more resolution usually means needing more GPU. But this being VR, I'm wondering how likely I am to see diminishing returns due to CPU bottleneck. Am I damned to replacing both? At this point a new CPU means a new mobo too... thus begins the budget death-spiral.

 

When I had my i7-5960X, I went from a 980ti to a 1080ti, and the performance difference in DCS was like night and day. You may get similar results going to a ti card in VR.

[X-31_VECTOR]

Hi,

 

 

I have a Reverb G1, 7700K@4.7GHz ,a 2080TI, 32GB RAM and two SSDs Raid0 solely for DCS. According to VRFPS the frametimes of the CPU are about 22ms and the frametimes of the GPU 12ms so I guess your future system would also have a cpu bottleneck.

 

 

My frame times with my 6700K running at 4.2 are not very far off from yours, actually. What's vexing to me is that CPU and GPU utilization are never maxed out, but someone pointed out that the CPU utilization shown in FPSVR may be averaging across cores and thus masking a single-core bottleneck. This gets into the dark arts of VR behind the curtain, which I do not claim to understand.

 

So a better GPU helps at high res, but you need a good cpu to stand a chance at realising those frames in the first place. See how hard you can overclock that 6700k!

 

Makes sense, and thanks! I know my 6700K 4.0 CPU should go well faster than 4.2, but despite having set a voltage limit in the ASUS utility (AI Suite 3) and/or bios, I get scary voltage spikes when I do go higher. Any suggestions for a better utility for managing my overclock? I'm on an ASUS Z170 board if that makes any difference.

[Taz1004]

My frame times with my 6700K running at 4.2 are not very far off from yours, actually. What's vexing to me is that CPU and GPU utilization are never maxed out, but someone pointed out that the CPU utilization shown in FPSVR may be averaging across cores and thus masking a single-core bottleneck. This gets into the dark arts of VR behind the curtain, which I do not claim to understand.

 

 

 

Makes sense, and thanks! I know my 6700K 4.0 CPU should go well faster than 4.2, but despite having set a voltage limit in the ASUS utility (AI Suite 3) and/or bios, I get scary voltage spikes when I do go higher. Any suggestions for a better utility for managing my overclock? I'm on an ASUS Z170 board if that makes any difference.

 

HWMonitor has always been the popular OC monitoring software.

 

You would need reliable power supply and cooling solution for good overclocking. But if you have to spend money for those, then it would make more sense to get i7-7700k. Just stay with stable and safe OC for now.

 

Just hold off any purchases until 3080 comes out. We don't know how well it will perform, how well it will perform with DCS, how much it will be, and how much lower 2080 will be.

[X-31_VECTOR]

HWMonitor has always been the popular OC monitoring software.

 

You would need reliable power supply and cooling solution for good overclocking. But if you have to spend money for those, then it would make more sense to get i7-7700k. Just stay with stable and safe OC for now.

 

Just hold off any purchases until 3080 comes out. We don't know how well it will perform, how well it will perform with DCS, how much it will be, and how much lower 2080 will be.

 

Thanks Taz! My CPU temps rarely go over 60C, so I've got plenty of headroom there. And good point on the 3080; I imagine some used but perfectly good 2080Tis will go on the market when the 3080 comes to town and upgrade fever hits.

[Eldur]

I was just about to say up the GPU as well and crank the CPU clock up.

 

Your 6700 literally has the same IPC (instructions per cycle) as the 9900k and even the 10x00 models which are just about to be released. Since DCS doesn't use any of the other cores at all (let alone HT which often is recommended to be switched off even), there's literally no benefit from a new CPU except for it running at a higher rate.

 

Makes sense, and thanks! I know my 6700K 4.0 CPU should go well faster than 4.2, but despite having set a voltage limit in the ASUS utility (AI Suite 3) and/or bios, I get scary voltage spikes when I do go higher. Any suggestions for a better utility for managing my overclock? I'm on an ASUS Z170 board if that makes any difference.

 

I don't use any tools at all, just increased the multi within my BIOS/UEFI for my 3570k. Didn't change the voltage though. Now the question is why do you get those spikes? Hard to tell, could be the board or PSU most probably...

[BeastyBaiter]

At this time you don't have an upgrade option that makes sense. If your CPU can hit around 5.0 GHz, you're doing fine on that front. If it falls short at maybe 4.5GHz, then a CPU/Mobo upgrade maybe your best action if you want something today.

 

If you can get to around 5 GHz on the CPU, then the GPU needs replacing. The problem is, the 1080 = 2070 Super or close enough to it. Additionally, a new generation of GPU's is coming in the next few months from both Nvidia and AMD. So I cannot recommend buying a high end GPU right now. The performance boost just isn't there at the moment and they will soon be replaced by things that are hopefully a lot better than the 20xx series have been.

 

 

As a side note, I have a 2080 Super and previously had a 1080 Ti. Long story as to how that happened, but trust me, that isn't really an upgrade. I know your 1080 is a bit less capable but honestly I recommend waiting at this point. In fact, rumor has it the 2070 Super and up are no longer being produced.

[X-31_VECTOR]

I've heard the same RE 2070/2080 production. Okay, the plan is wait for the 3080 cards and see what they deliver, and meanwhile revisit the CPU overclock. It's a shame DCS only uses a single core.

 

Interesting thoughts regarding the power supply maybe being behind the voltage transients. I have an 850W EVGA rated 80+ Bronze, and I recently hooked it up to a PSU tester to confirm all the voltages going to the board were within spec. So I suspect this has more to do with the board or Asus OC software. I'll try some different methods and report back. Thanks all!

[CobaltUK]

Probably a long way off but code changes expected ought to mean exotic hardware will no longer be needed to the same degree.

 

Annoyingly today i boosted my steady clock speed by 1/2 GHZ (not overclocked) via a cpu change (and just as importantly sorted out the cooling so never any throttling under load) only to have for the 1st time pauses and actually lower fps under same situation/settings. PSU is over sized.

FpsVR shows the pauses and cpu frametime solid red most of the time at anything but low settings. Very odd and very annoying.

[Taz1004]

I've heard the same RE 2070/2080 production. Okay, the plan is wait for the 3080 cards and see what they deliver, and meanwhile revisit the CPU overclock. It's a shame DCS only uses a single core.

 

Interesting thoughts regarding the power supply maybe being behind the voltage transients. I have an 850W EVGA rated 80+ Bronze, and I recently hooked it up to a PSU tester to confirm all the voltages going to the board were within spec. So I suspect this has more to do with the board or Asus OC software. I'll try some different methods and report back. Thanks all!

 

Unless it's extreme, voltage spike is normal. Even default clock, voltage sometimes spikes to 1.4.

[Waxer]

Friend of mine and I have been comparing benchmark results in DCS with our similar, but different systems. He has 6600K@4.6, 32GB DDR3 with 2080Ti. I have 7700K@5.1 32GB DDR4 3600 with 1080Ti. We both have Pimax 5k+.

 

I generally beat him in FPS, as it mostly comes down to CPU. However, he can afford to push supersampling and MSAA, while I can afford neither.

So don't expect a new GPU to give you lots of extra FPS, but it seems it can certainly help with attaining higher resolutions and image quality.

For example, we both normally run normal FoV (medium), but when we go to maximum FoV, he loses only half the FPS that I do.

 

So a better GPU helps at high res, but you need a good cpu to stand a chance at realising those frames in the first place. See how hard you can overclock that 6700k!

 

Good / useful post. I am on an RTX 2080 Ti and CPU at 4.8GHz. I am in that kinda no-mans zone where CPU upgrades will be noticed, but ever so expensive for a fairly minor performance boost. And GPU... well who knows what Ampere and RDNA2 bring...

[X-31_VECTOR]

Unless it's extreme, voltage spike is normal. Even default clock, voltage sometimes spikes to 1.4.

 

Issue fixed: I was letting the BIOS automatically manage the voltage, and even though I had set a cap through Asus software at 1.3, the voltage would still go on crazy excursions above 1.4.

 

Once I turned off the auto management in BIOS and just set it manually, the voltage stayed rock steady at 1.3 and I'm currently dead stable OC'd to 4.6 with no temperature issues. I'm hoping to get it to 4.8.

 

The case seems pretty clear now that a CPU upgrade for DCS/VR doesn't make sense for me. More money for the GPU upgrade when the 3080 family lands.