How to figure CPU limiting, and GPU upgrade

ibriggs

Distinguished
May 1, 2007
4
0
18,510
Hey guys,

I have a gaming computer I built about 3 years ago, I'm looking for a way to milk another few years out of it. Still, with most GPU upgrades I've been looking at, I keep running into the same question "will my CPU make a new GPU a waste of money?"

Heres my current rig:

AMD 3800+ X2 Dual Core
2 Gigs Corsair XMS DDR2 ram
2 x 6800 GT Running in SLI

I can run source games flawlessly, FEAR with decent framerates, and AOE 3 with decent framerates. Oblivion runs pretty smooth as well. Still, having two GPUs has its downsides. Primarily its hot and noisy, not to mention adds weight and clutter to an already packed case. In short, I'd like to upgrade and downsize to ONE newer GPU, but haven't been able to find many straight-forward answers about a CPU limiting the performance of a GPU. Obviously I know it happens, but to what degree? The bottom line is, I'm not planning on building a new gaming rig any time soon so you can skip "just save up for a new rig." I've decided this computer can last me another 2 years even if I can't play Crysis (GASP) but wouldn't mind a GPU that will allow me to play games that aren't as demanding as Crysis for a little while longer. Specifically RTS games, and games with highly scaleable graphics where I could still have fun playing it even if it didn't look as nice as my 360 or high end rigs.

thanks in advance
 
Hello and welcome to the forums mate :)
X2 3800 @ 2.0 will bottleneck a new GPU but if OC your CPU to 2.6 or more then it will be fine and then u can add a new VGA like 8800GT and u will be fine
 

pauldh

Illustrious
Yeah, I agree with stranger. You may not get the absolute maximum measureable performance with your cpu, but tweaked to max playable settings it's the gpu that will be your limit most of the time. I myself wouldn't hesitate to put an HD3850, HD3870, or even the 8800GT in that system. There is no reason you can't play every game out there including Crysis with that rig.

Take a look at this review of budget gaming. Notice while there is a measureable difference at lower resolutions, even with the pretty amzing 8800GT the X2 4000+ hangs with the C2 extreme at higher res.

The 8800GT is the bottleneck at 16x12 4xaa/16xaf in COD4:
http://www.firingsquad.com/hardware/$500_gaming_pc_upgrade/page5.asp

Same with UT3:
http://www.firingsquad.com/hardware/$500_gaming_pc_upgrade/page6.asp

And Crysis also:
http://www.firingsquad.com/hardware/$500_gaming_pc_upgrade/page7.asp

You may find that in very cpu demanding areas of games (town gates with lots of NPC's in Oblivion or your RTS games) that the CPU is causing your min framerates to be lower than the higher end CPU's. But overall, I would not let the fear of a cpu bottleneck stop you from buying a great card like the 8800GT.
 

gpippas

Distinguished
May 11, 2007
463
0
18,790
Basically what strangestranger said. There is no exact science as to the bottleneck phenomanon. It can vary a lot depending on the game, resolution, textures etc.

My advice is 2 years might be a little optimistic but it is purely a matter of opinion. The only advice I would take from maziar is overclocking the cpu would help. Search on the forum or google as there are some good guide3s to overclocking K8's. At a minimum you should be lokking at 2.6ghz. Your max should be from around 2.7-3.1ghz depending on your other components and luck.

Graphically a 3870/3850 512mb/8800gt 512mb will do you fine and see a decent performance increase over your 6800gt's. Don't go for any 256mb cards because the extra memory is starting to become more useful. Don't bother with any more dual card setups because they are a pain and the performance isn't worth it.
 
complete and utter bollocks, do not listen to this tosh.

if you lower your res down to 800 x 600 and details low, do you get unplayable fps, if so then you have a cpu bottleneck, if not then you are gpu limited simple, cpu limitation and bottnecking are two very different things.


so if i am wrong then u say that a X2 3800@stock wont bottlenck a 8800GT ?
 
complete and utter bollocks, do not listen to this tosh.

if you lower your res down to 800 x 600 and details low, do you get unplayable fps, if so then you have a cpu bottleneck, if not then you are gpu limited simple, cpu limitation and bottnecking are two very different things.

i think i havent undertand exactly what he said but u say that a X2 3800@stock wont bottlenck a 8800GT ?
also talk more politely, we try to learn from each other not to laugh and insult each other
 
maziar, take a look at your broad, sweeping statement. now, read the op's post and tell me if you think what you said makes any sense at all.

no it doesn't, the main mistake you make is that a cpu cannot, i repeat cannot bottleneck a gfx card, it can bottleneck a system's performance but even then it has nothing to do with the gfx card, it is to do with the app that the cpu is trying to run, nothing else, no other piece of hardware only software.

now, while a slower cpu will make a difference in performance, i do not think the op will mind that as except in the newest games his cpu will be fine. even then, whether or not the performance difference between the different cpu's would be noticable to the op is debatable and only they could answer that.

Sorry stranger but with respect i think your being pedantic about this. To say that a CPU cant bottleneck a GPU but it can bottleneck a systems performance whilst having nothing to do with the graphics card is ridiculous.
Can an underpowered CPU restrict the frame rates in games: YES 100%
What part of the system is being restricted: The GPU
And to try and separate software from hardware with this statement "but even then it has nothing to do with the gfx card, it is to do with the app that the cpu is trying to run, nothing else, no other piece of hardware only software." seems a bit weird to me doesnt the one rely on the other?

I know it sounds like I'm having a go but I'm just trying to point out that you are calling Maziar for making sweeping statements by making your own.
The term "Bottleneck" when used to describe a performance restriction seems to upset some people but its how most people understand it best, It really is a very complicated issue and you were right to call Maziar about his statement as any number of factors from games played to monitor size/res to name just a couple can all make a differance.
Mactronix
 
For games that are graphics intensive, a better vga card will help with either better quality settings or fps. For purely cpu intensive games it won't help. Most games have some of each characteristic, so I would look forward to some improvement. I don't see how it could ever hurt, and a good vga card can be moved easily to your next system.

I see that you have 2gb of memory. Some games can use more than 2gb if you have it. If you suffer any hard page faults at all, it will act just like you had a slower cpu. With memory so cheap these days, consider adding 1 or 2 gb to your system.


 
Well the thing is that you are 100% right but what can you do? Maybe you should have a word with one of the Mods and see if you can put a sticky on the forum about it ?
Thing is as i said most people will call it a B******* and thats the way they understand it so you can either keep banging your head against a wall and try to get people to understand what you are saying or just supply them with the best advice you can.
Cheers Mactronix
 

ibriggs

Distinguished
May 1, 2007
4
0
18,510
Hey guys,

I appreciate the feedback. Here's what I garnered from what y'all have said.

A: CPU Limiting

There doesn't seem to be any of you who would say it would be a complete waste to put a 8800 GT in my rig due to "cpu limiting." Rather, I might find that I can't get the SAME framerates (depending on the game, of course) as the toms stock setup, but will DEFINATELY see an improvement no matter what if I upgrade my GPU.

B: Overclocking

Overclocking would be an integral part to getting the most out of a new graphics card, simply because most newer games simply demand more from the CPU. This does not, however, imply that the GPU and CPU are so tightly related that I would need both to be at a similar level of performance.

C: RAM

Someone mentioned putting extra sticks of RAM in my rig. Am I right to say that most games do NOT recognize more than 2 sticks? And also, most applications and Windows itself doesn't recognize more than 2 sticks? I'm a bit late on my information, its been a while since I was more read up on this stuff...
 
The number of sticks of ram is relevant only to single vs dual channel operation. Dual channel is a bit faster, so you need an even number of sticks. An individual 32 bit application can normally see 2gb of address space, a 32-bit os can see the other 2gb of address space. You can have several applications running at the same time. If they compete for the 2gb of ram you have, then demand paging occurs, and virtual memory is swapped in and out to the hard drive. That is very bad for performance if it happens much. Some games will try to use more than 2gb if it is there, but I don't think that is common. Look at the recommended configuration for the games you like to be certain. If you get an e-mail, or a virus scan starts up while you are gaming, you will notice a lag if you do not have sufficient memory. Start the performance monitor to see what you have runniing in your system at any one time.
 
maziar, take a look at your broad, sweeping statement. now, read the op's post and tell me if you think what you said makes any sense at all.

no it doesn't, the main mistake you make is that a cpu cannot, i repeat cannot bottleneck a gfx card, it can bottleneck a system's performance but even then it has nothing to do with the gfx card, it is to do with the app that the cpu is trying to run, nothing else, no other piece of hardware only software.

now, while a slower cpu will make a difference in performance, i do not think the op will mind that as except in the newest games his cpu will be fine. even then, whether or not the performance difference between the different cpu's would be noticable to the op is debatable and only they could answer that.

well if u r right and a CPU wont bottleneck a VGA, then why doesnt someone put a 8800GTX with a P4 ??
i really want to know this and no jokes
 

rickpatbrown

Distinguished
Feb 17, 2007
117
0
18,680
Because for 500 bucks, you could get a new motherboard, ram and a new processor. An 8800GTX would still help the p4 system though.

Is the analogy of the CPU being another link in the chain accurate. That would imply bottlenecking. Or is it more an umbrella type of thing?
 

Can Not

Distinguished
Nov 11, 2007
236
0
18,680
OK, here is the plan.

Buy an 8800GT ($280) right now. Buy a new motherboard and processor ($600 maybe?) 1 to 3 years from now. GG.

uh...maybe buy a PSU, too.
 

pauldh

Illustrious
Some games are more CPU bound than others. In Fear, (within reason) the CPU means little, it's pretty much all GPU bound at playable settings. In Flight Sims or RTS games the CPU can mean alot. It's best to have a balanced system to assure smoother/better gameplay in general in any game you may want to play.

But it seems many people overlook the importance of the GPU in gaming. Probably because of the marketing of the big oems that have pushed processor MHz, features, or now cores for sales, and skimped (and deceived the average Joe)on other important system components like a decent GPU. Given the option, in a gaming rig I will skimp on the CPU before skimping on a GPU. Any athlon X2 or C2D can put up a decent gaming expereince, but integrated or low budget GPU's usually won't. I'd take an X2 3800+ / 8800GT anyday for gaming over a Q6600 /X1550 or GF7200.
 

ibriggs

Distinguished
May 1, 2007
4
0
18,510
Thanks guys, ordered an 8800 GT today, I will do a before and after run of 3dmark and post it. I think its obvious to everyone, however, that I will have a better run AFTER putting the new card in than before.
 

sepayne21

Distinguished
Aug 15, 2007
225
0
18,690
complete and utter bollocks, do not listen to this tosh.

if you lower your res down to 800 x 600 and details low, do you get unplayable fps, if so then you have a cpu bottleneck, if not then you are gpu limited simple, cpu limitation and bottnecking are two very different things.


He is on the right track in some games but not all, I ran the timedemo for crysis at 800x600 at min graphics settings to check to see if my processor was the bottleneck (3800+ x2 @2.3 8800gt sc) and got something like 32fps. Then I tried increasing the resolution up to 1280 x 1024 and got like 60 fps. then I maxed out the eye candy (except for AA) and got something like 44 fps. some games play better with a higher resolution than a lower one. What he needs to do is try to find the optimal resolution where he gets the highest framerate, then lower the eye candy to it's minimum. If he then finds the game to be unplayable, it is probably his processor.

Another way to check is to bring up the task manager before you start a game. Then ctr+alt+del in the middle of the game and look at your cpu history. if the cpu is using 100% and you are still getting poor framerates at low graphics settings, you'll need a more powerful processor.

I might be cpu bottlenecking a little bit with my setup, but with all of the new games comming out being optimized for dual core support, it's fast enough to give 60+ framerates in all of my games except crysis.

I think you'll be alright getting an 8800gt as long as you have a dual core processor, but either way I'd overclock your cpu.
 

xunicronx

Distinguished
Nov 2, 2007
292
0
18,810
StrangeStranger, don't be a douche bag. I hate people like you that think they know everything about computers. Dell forums have people like this, don't turn this forum into a Dell forum. Just be cool.
 

MrCommunistGen

Distinguished
Jun 7, 2005
1,042
0
19,310
The main issues here are:
1. YES getting a card in the 3870/8800GT range will help a LOT even if it is the only component being upgraded.
2. It would help more on a faster CPU, but overclocking will certainly help.
3. A GPU upgrade will give far more improvement over an "equivalent" CPU upgrade (say to an E6850 or a Q6600 @ 3.0) where the OP keeps his original GPUs

Of course a stock X2 3800 will bottleneck a fast GPU, but that does not change the fact that *on the same CPU* a GPU upgrade like the one being suggested here will translate to smoother and higher framerates.
An example: My rig runs Oblivion pretty poorly. My CPU (like the OP's) will definitely hold back a card in the 8800GT range. I will *still* get a HUGE improvement if I upgraded to an 8800GT.

Edit: As was mentioned earlier the term bottlenecking IS used too much. All it means is that not all the components are perfectly matched to each other and that something is holding something else back from performing to its fullest. It would be very difficult if not impossible to make a system that did not have a bottleneck somewhere, especially since games have varying degrees of CPU or GPU dependence.

-mcg
 

3Ball

Distinguished
Mar 1, 2006
1,736
0
19,790


I thought I would help you out with a little advice that I give to most people who have concerns with "bottlenecks". I dont want to discredit anyone else in the thread, but it sort of has taken on another direction in my opinion. When buying your graphics card it is best to just get the best one you can afford if you are someone who plays alot of games and you arent going to be spending any more money on anything else (As in...the saved money from a lesser GPU will help lead to some other part that will boost you overall system performance). Will you get more frames with a faster CPU...yes, but you will also get better frames out of an 8800GT than you will say an X1900XT with your cpu or not. So what I would do if I was you is go ahead and get that 8800GT. If you want to OC and have the capabilities to do so then go for it and yes it will help, but it is up 2 you if you need the extra performance or not. I probably would if I was you. I would probably take it to 2.4 - 2.6ghz and make sure that is was 24+ hours orthos stable and then just go along and play my games.

To sum it up. Get the best card you can and just go from there. Will you get the best possible performance out of it...no, but you will still get better performance than a lesser card. Hope this helps!

Best,

3Ball
 

3Ball

Distinguished
Mar 1, 2006
1,736
0
19,790


When I wrote what I said I had not read your statement. To the OP. Mine and his are pretty much the same thing. Take what you will from both. I think this way of thinking will help with alot of the decisions in this industry.

Best,

3Ball
 

Can Not

Distinguished
Nov 11, 2007
236
0
18,680

Yeah, after I already said that.
 

Ilander

Distinguished
Jul 22, 2007
173
0
18,710
http://www23.tomshardware.com/cpu_2007.html?modelx=33&model1=942&model2=882&chart=418

That's what happens when you put a fast gpu with a slow processor.

You're going to lower your maximum frame rate to a set number dictated by your processor in each game, but if you set the graphics settings high enough, you'd be at that number anyway.

Look at my config. I only score about an 8900 on 3dmark06 (http://www.tomshardware.com/forum/247495-33-fastest-system-gaming-world)

BUT, I can play UT3, Crysis, Quake Wars, Team Fortress 2, and Call of Duty 4 at max settings at 1280x1024, and my processor doesn't slow them down, because it can feed my video card data fine at that rate.