PDA

View Full Version : GPU or CPU bottleneck?



Pancakewaffles_
11-28-2014, 04:38 AM
Hello,
I am looking to upgrade my PC to be able to play AC Unity at a more reasonable frame rate. For those who are able to play the game more decently is it more bounded by CPU or GPU? With my current specs I am only looking at 20fps with a lot of stuttering. :( I am considering to upgrade only either the CPU or the GPU. Hence my question.

PC Specs:

CPU : Intel Core i5-650 @ 3.2Ghz (It is a Clarkdale LGA1156, pretty old dual core)
GPU : Palit GTX 680 Jetstream 2gb VRAM
PSU : Aerocool 750W
RAM: 2 x 4GB Kingston DDR3-1333
OS : Windows 7 64bit

Thank you!

jorimt
11-28-2014, 05:02 AM
Out of the two, your CPU is definitely the first thing to replace. Unity relies quite heavily on the CPU, and unlike previous AC games, it scales better to 4+ CPU cores.

If you're looking to upgrade your CPU for gaming, I recommend something like the i5-4690K. 4+ cores are a must in current-gen PC games, especially if you intend to pair the CPU with a mid-high end GPU, and not run into any bottlenecks.

As for your GPU, the only issue you're going to run into is the lack of VRAM. At "High" texture settings, Unity requires an average of 2.4GB VRAM, so, if you haven't already, you need to set your textures to "Low." Some of the stuttering on your currrent setup could be due to setting the textures too high, unless of course, you're already at the "Low" graphics preset.

Altair1789
11-28-2014, 05:03 AM
I think your CPU is the problem here

D.I.D.
11-28-2014, 05:09 AM
I have a GTX770 4GB. I was tempted to trade up for a 970 before Unity came out, but I needn't have worried. I play Unity at 1440p with all effects switched on and everything on Ultra High, except for shadows which I have on High. The game is still perfectly playable on the top rung for shadows (soft shadows), but I don't feel like it really adds enough to the game visually to make it worthwhile, and there's a little frame rate hit which makes details like roof tiles less distinct when roof-running, and my eyes like that stuff. I found that TXAA was too much for my card too, but it's fine with FXAA and I'm not seeing any edge problems.

Your GPU is pretty much the same as mine, aside from the VRAM, although my 770 has a small factory overclock (but I don't think that's making a major difference here). As you know, your CPU's type and features are more important than its on-paper speed, and yes, this game's very intensive. The recommendations for a quad i7 were unnecessary, though. This game does not use hyperthreading, and I doubt we're going to see any games that do for years to come. A decent i5 from a recent generation will be fine: i5 4440, i5 4670, or anything like that is unlikely to drastically bottleneck a GPU during the next handful of years.

There's no point in tracking down an old CPU for your motherboard. Get a new motherboard and a new CPU, whatever seems like a good balance for the money, and you'll need a new Windows too so bear that in mind. New games are beginning to routinely creep just over the 2GB usage, and since other features like antialiasing also make use of VRAM, so you will eventually want to get a new 4GB card. That said, I would wait, if I were you. We're still at a point where the latest and best cards can't give a decent performance at 4K unless run in SLi. The Maxwells do have some really nice unique features, and they've made some miraculous jumps in output and extremely low power consumption, but you still have an excellent card there for 1080p gaming.

USAdystopia
11-28-2014, 06:25 AM
NOT necessary to change your OS unless you are using the Home or Basic versions. You can use the Windows 7 Optimization Guide on thessdreview to increase your performance substantially. See if you can incrementally increase the settings on your gpu...monitor temps.

Be sure all drivers and your BIOS are the latest for your hardware.

Be sure that ALL "High Power" settings are enabled in Windows, ssd and mobo software.

If you can afford it, new mobo and cpu would be of benefit for ALL your games. Memory is OK but either get 8 MORE gigs of the exact version you own or get new 16 GB or more 1600/1866 sticks (if compatible with mobo).

Pancakewaffles_
11-28-2014, 06:59 AM
Thanks everyone for their input! Have purchased a new CPU + MOBO (took advantage of the Black Friday deals :D). I am getting the i5-4690K + ASUS Z97-Pro and they would be delivered in about a week's time. Hopefully my gameplay will improve! See ya guys in-game!

D.I.D.
11-28-2014, 07:32 AM
NOT necessary to change your OS unless you are using the Home or Basic versions. You can use the Windows 7 Optimization Guide on thessdreview to increase your performance substantially. See if you can incrementally increase the settings on your gpu...monitor temps.



When Windows 7 detects that new CPU and motherboard, those hw pieces are going to trip too many "points" and Windows will see it as too significant a hardware change. If the OP owns the original Windows and it was the full retail copy, he/she might be able to transfer the licence to this new system. If it's an OEM, which it will be if the OP bought the PC from a system builder, then the OP is very likely to need a new Windows.

Windows's sensitivity has always been a bit of a mystery, since sometimes it's okay about big changes and weirdly sketchy about tiny ones, but this is all a side issue. I'd advise budgeting that little bit extra to switch 7 for 8.1 anyway, just because it's really good. The amount of hate it gets and the amount of praise 7 gets are completely disproportionate to each OS's experience. If someone made me go back to 7 now, good though it was, I'd be unhappy about it.

Win8.1 and an SSD could be added for 110 at the low end, which isn't a tiny amount of money but it would make a big difference.

jorimt
11-28-2014, 05:14 PM
Thanks everyone for their input! Have purchased a new CPU + MOBO (took advantage of the Black Friday deals :D). I am getting the i5-4690K + ASUS Z97-Pro and they would be delivered in about a week's time. Hopefully my gameplay will improve! See ya guys in-game!

Glad to hear, good choices ;)

EdgarFriendlier
11-28-2014, 05:59 PM
I recently upgraded my CPU from an i3 4130 to an i5 4460.

I already had a GTX 970 4GB.

With the i3 and everything on ultra except AA on FXAA, I was getting 30+ FPS.

With the i5 and everything on utlra except AA on FXAA, I'm getting 40+ FPS.

In both cases, FPS is at its lowest in heavy crowds, high on rooftops, and very high indoors.

The game was quite playable with the i3. I was just curious what kind of an improvement I would see with an i5.

Johny-Al-Knox
11-28-2014, 06:47 PM
The game scales very good infact. its using all of my 12 threads on my 6 core processor, atm im gpu bound, got 2x 970's(running mostly 60 fps ++,expect in crowds it can go to 50). So it really depends. If its using all of ur current gpu, buying new cpu wont help. but in the other hand if u buy a new GPU and u get cpu bound u need to buy new cpu:p Eitherway ur current cpu deserves an upgrade u will benefit from other games.