Is my Q9400 bottlenecking my ATI 6870?

rpeters83

rpeters83

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My desktop is a Dell XPS 630i with a Q9400 and ATI 6870 (8gb ddr2 1920x1080). I also have a newer laptop with a Core i7 and nvidia 640m (8gb ddr3, 1600x900). The annoyance that I currently have is, my laptop plays most games better than my desktop. Double the framerate, in some cases.

Obviously my desktop is several years old, but I didn't think that a laptop with a slower GPU would play better than my desktop with a better GPU. From a search, I see mixed results as to whether my 6870 is too much for my Q9400, but can't come to a conclusion.

I'm otherwise content with the non-gaming performance of my desktop, so I'd hate to build a new PC and not get performance that is leaps and bounds better than before.

So, is my stock Q9400 really a bottleneck? Would I get much greater performance with the same card in a new Core i7 build? Or, did I read things wrong and the 640m is better than the 6870? Thanks.
 
So, is my stock Q9400 really a bottleneck?
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The answer is yes, even OC'd the answer is still yes.
I don't know if just uprading to an i5/i7 is enough performance increase to justify it alone, though.

Some people here will tell you otherwise, don't believe them. i7's going all the way back to the 920 (OC'd) are still carrying their weight... C2Q's are not.
 
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yes it would hold even a 6870 back but it should not be bad enough to impact gameplay unless you are trying to stay above 60 fps. and doing that is not possible on 6870 anyway in most newer games unless running greatly settings. and at 1080, its a almost guaranteed that your 6870 is going to be the limitation.
 
It's not fair to compare 1600x900 to 1920x1080. It doesn't sound like much of a difference on paper, but it's actually really big.

The q9400 is a very easy CPU to overclock and runs cool under even the stock cooler. Bump up the multiplier and 2.8ghz is a cinch. 3.2 or 3.4 is very reasonable with a stock cooler too. It won't be close to an i7 but it will open up that video card some.
 
yep 1920x1080 is 44% more pixels to drive. with a 6870 you will pretty much lose almost that much in most graphically demanding games since you will already be gpu limited at 1600x900.
 
Depends on the title as ever, but one thing to remember is that when your GPU can't keep up, you can just turn the resolution and/or detail down. When your CPU can't keep up, there's often not a lot you can do about it.At 1600x900 the HD6870 is modestly capable - after all, at that res an HD6870 is roughly equivalent to:
An HD6970 at 1920x1080
An HD7850 at 1920x1200
An R9 290 at 2560x1600
Two R9 290s at 3840x2160

Given the sort of frame rates you see in games in such configurations, I'd say you're probably more likely to be CPU limited in newer titles than GPU limited. You'll definitely not be using maximum detail if you want to see 60fps continuously, but I think a CPU upgrade would do you good. It needn't be amazingly expensive, a current-gen i5 such as the 4570 offers a solid 80-90% increase in processing power versus your Q8400, on a slightly more favourable power/heat footprint.

Either way, I could certainly say that upgrading your graphics without upgrading your CPU first or at the same time, is the wrong move.
 
cannondale06 said:
yep 1920x1080 is 44% more pixels to drive. with a 6870 you will pretty much lose almost that much in most graphically demanding games since you will already be gpu limited at 1600x900.
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This.

You're comparing apples to oranges. I have a 640M in my I-7 Ivy Bridge laptop, it runs many games fine, but you can't compare 1600x900 to 1920x1080.

And I find it highly unlikely that you're CPU bottlenecked and if you actually are, it would be in games like BF3-4 or WOW where you're running on large servers which is very CPU intensive. The C2Q are still ok chips, but there are defiantly upgrades to be had. I have a [email protected] my son still uses to game on and it does not bottleneck a Radeon 6970 in most games. Open your resource monitor in game and check your cpu usage.
 
Pitbully said:
This.

You're comparing apples to oranges. I have a 640M in my I-7 Ivy Bridge laptop, it runs many games fine, but you can't compare 1600x900 to 1920x1080.

And I find it highly unlikely that you're CPU bottlenecked and if you actually are, it would be in games like BF3-4 or WOW where you're running on large servers which is very CPU intensive. The C2Q are still ok chips, but there are defiantly upgrades to be had. I have a [email protected] my son still uses to game on and it does not bottleneck a Radeon 6970 in most games. Open your resource monitor in game and check your cpu usage.
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low cpu usage will not mean you are not cpu limited though. some games use very little of the cpu but need more speed or more cores or both to perform better.
 
Thanks for the replies. Here's one example. I'm playing the Black Mesa mod on Stream. I plugged my laptop into my 1080p monitor the other day and did a comparison. In one scene, at the same resolution and settings, the laptop with the Core i7 and nvidia 640m was getting 60 fps and my desktop with the Q9400 and 6870 was getting about 35.

So, even at matching resolution, the laptop with the technically-slower GPU is destroying my desktop.
 
Black Mesa has problems with CPU's usually related to quad cores. There's a bunch of tips around the web about messing with affinity and it supposedly helps but I wouldn't use it as a benchmark.

If you really want to be shocked then try firing up GTA 4. Also a bad benchmark in terms of port quality but it will emphasize any CPU-related bottlenecks you have.
 
TaintedSquirrel said:
Black Mesa has problems with CPU's usually related to quad cores. There's a bunch of tips around the web about messing with affinity and it supposedly helps but I wouldn't use it as a benchmark.
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Thats most likely a Source Engine issue and not the game itself
 
I ordered a new rig today:

i7 4770
16GB DDR3
TX650 PSU

I plan on using the same 6870. I'm going assume that my GPU will now be the slow part in this equation, but will it run much better going from a stock Q9400 to a i7-4770 and DDR3? Hoping I'm not wasting money. Thanks.
 
Congrats on the new rig! :)

And yes, that 6870 is now the weak part. But maybe 1920x1080 will be tolerable if you're conservative on the settings.
 
Darksword said:
Congrats on the new rig! :)

And yes, that 6870 is now the weak part. But maybe 1920x1080 may be tolerable if you're moderate on the settings.
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Thanks.

So, I WILL see a general improvement with this new setup? I really would hope so...

Sorry for sounding paranoid. Just trying to justify my purchase. I'm cheap :)
 
I think it's justified. I just upgraded to a 4770K from an i7-930. :) I got a boost in performance for the games I play, and having SATAIII is a nice boost. Are you using an SSD in your new build?
 
lloose said:
It's not fair to compare 1600x900 to 1920x1080. It doesn't sound like much of a difference on paper, but it's actually really big.
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This. The comparison is that there isn't one at this point. Unless you're playing at equal resolutions and settings there is no definitive answer and it's all just speculation.


I've owned a Q9550 since March of 2009 with a GTX 260 and there was NO bottlenecking whatsoever on the CPU side. Newer games, higher resolutions, and higher settings put more stress on my GPU than my CPU and to squeeze another 1 1/2 years out of my CPU I did a fairly easy 1Ghz OC, which did work wonders. Even when I upgraded to a 660 before the rest of the system, I saw some drastic performance increases. This case is very different because the hardware discrepancies. Also there has to be a common benchmark to determine FPS. Not just lows or highs, but the averages which are more important.

I'll also second that the Source Engine has some issues, especially with Black Mesa. It's a hack job implementation of supporting multi-core processors and really only TF2 gets the Source Engine love.

A system upgrade will help your system either way though. Whether it's necessary depends on you.
 
C2Q's are still decent CPU's, but not worth dumping money into. I had a 6870 with a 2500k at 4.7ghz, playing MWO at 1080p with everything maxed except AA (had it turned off) I got around 25fps in heavy fire fights, 40-60fps when running around depending on the map. So expect around that with your new setup.
 
A few pointers on this:


The HD6870 is roughly 50-60% more powerful than both the GTX260 in Liger88's post (assuming it's the 216-core, more like 70-80% if it's the original), and from what I can tell, seemingly about 50-70% more powerful than the GT640M in your laptop.

The Q9550 in Liger88's post is perhaps 15% more powerful than your Q8400. It might not sound like much, but it can make a difference.

I tested my HD6970 Crossfire setup with a Q9550 at 3.6Ghz, and my current i5 750 at 4.1Ghz. By my calculation that's about a 40% performance boost in CPU power. It made a tremendous difference. Now before it's commented that a crossfire setup with bigger cards is chalk and cheese to this, I was playing at 2560x1600, which is effectively double the requirement of 1920x1080 (97% more pixels). Given that crossfire scaling isn't perfect, it's not dissimilar to one HD6970 at 1920x1080, which is perhaps 30% more graphics power than your HD6870. Long story short, I saw a big performance jump by upgrading my CPU for about 40% more power with the equivalent of a 30% faster graphics card than yours.

With an i7 4770, you're upgrading your CPU to the tune of about 110% more performance.

Black Mesa is very poorly optimised. The same PC that plays Left 4 Dead 2 at 150-250fps continuously, played Black Mesa at around 35-60 at the same settings. Numerous people who had no other issues with their PCs reported problems with frame rate drops in odd particular sections of that title, as did I. It's not a properly released title like the other Source engine games, it's a long-overdue community project that was shoved out the door 'mostly done'.
 
Seems like you spent way too much money on upgrading your cpu/motherboard/ram while disregarding the gpu, sell your C2Q setup asap and look to upgrade that gpu, I'd suggest a 670 gtx which can be had around the $200 mark. Why did you need 16gb ram?

Hopefully the gpu upgrade will cost very little after selling the c2q setup and the 6870.
 
Yeah the GPU is definitely the next job but I'd see how you get on with the existing one first in the titles actually being played.
 
Thanks. Unfortunately I cannot overclock this stock Cpu so that is stuck at 2.66 ghz.
 
One point I forgot to mention - you have presumably checked your new equipment fits in your Dell system with the case and power supply? Dell units are usually proprietary, and people are often in for nasty surprises when they try and upgrade them.
 
I'm getting a whole new system. My wife will get my old one with an older 9800gtx.
 
Here's another example. WoW plays terribly on my desktop, but flies on my laptop. I also got Total War: Rome II and it plays better on my laptop than my desktop. That to me is the CPU.

Also, in case it was missed, I did plug my laptop into my 1080p screen and it still killed my desktop. The screen resolution argument between 1600x900 and 1920x1080 didnt make much difference in my case.

So, in conclusion, I should see some improvement? Thanks again for the replies.
 
Yes you should, and further - WoW is pretty much all CPU these days as well I believe.
 
I would say that your core2quad is absolutely bottlenecking your 6870. But if you need some hard numbers, Tomshardware recently did an article that pit core2 against ivy bridge in modern benches:

http://www.tomshardware.com/reviews/ivy-bridge-wolfdale-yorkfield-comparison,3487-9.html

*they do use a graphics card that is notably better than yours, but you can get a sense for how much the architecture is improved in ivy bridge and beyond. Also, take a look at the non-gaming benchmarks. Core2 actually makes a decent showing, but you'll get a better overall picture of what the difference will be with a newer processor.
 
rpeters83 said:
Here's another example. WoW plays terribly on my desktop, but flies on my laptop. I also got Total War: Rome II and it plays better on my laptop than my desktop. That to me is the CPU.

Also, in case it was missed, I did plug my laptop into my 1080p screen and it still killed my desktop. The screen resolution argument between 1600x900 and 1920x1080 didnt make much difference in my case.

So, in conclusion, I should see some improvement? Thanks again for the replies.
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I was raiding on Q6600 during MoP earlier this year and almost got removed from my top-tier tanking position simply because my fps was causing problems.

Lowest I saw was 10-15fps on Heroic Tsulong. 10-man was ok most of the time, but 25-man forget about it.
 
TaintedSquirrel said:
I was raiding on Q6600 during MoP earlier this year and almost got removed from my top-tier tanking position simply because my fps was causing problems.

Lowest I saw was 10-15fps on Heroic Tsulong. 10-man was ok most of the time, but 25-man forget about it.
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I had the same issue back in cataclysm. All the benchmarks said my q9400 @ 3.2ghz would be great for 25s but it wasn't. I thought all CPUs would perform about the same and it was an engine problem but as soon as I upgraded to my i7 2700k, I saw an insane difference. 10-15 fps went to 25-60 with it dropping to 25 very rarely and stayed right in the 45 fps range a majority of the time. This was in 25s and LFR.

I know only a handful of places still use wow as a benchmark but I check those frequently because of it. I think they should include numbers from LFR because that part of the game is the true test of hardware.
 
About a week-ish into my new 4770 upgrade with the same card and I'm very happy. Yes, some games that depend highly on the GPU (like crysis 2, on extreme getting about 40-50fps) don't have much change to them (maybe slightly, but not noticeable), but other games, even simple ones like WoW, sanctum, source games, or even total war rome play leaps and bounds better now (usually double or triple the framerate from before, all on highest settings).

I think I'll stick with my card for a little until I have a more compelling reason to upgrade (I have two small kids so my time is limited).

Thanks for the replies.
 
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