What part of my computer do I need to upgrade for DX:HR?

March 3, 2012 6:51 AM

I have Deus Ex: Human Revolution installed via Steam. It runs perfectly... at 800x600. Any higher and it gets choppy. I can run higher resolutions with the lighting effects turned off. Does that mean I can make it better with a new graphics card, with more shading units or whatever you call it? Or is my old-ass Athlon X2 CPU more to blame?

My system infos:
CPU: Athlon 64 X2, family 15 model 75, which I think translates to model 3800+ in AMD language
Graphics: Radeon HD 4650 with 256MB VRAM
RAM: 6GB DDR2

I can get decent performance at higher resolutions by turning off SSAO and shadows. This is unpleasant to look at, because the game proceeds to paint shadowed areas with whatever shadowish texture will fit, causing the edge of Adam's coat to radiate dark auras. I'd be OK with that if the game could decide which direction the aura were radiating in, and it weren't the sort of half-assed dark aura that never even covers his chest.

If I need to upgrade the CPU to get any benefit, I don't think there's much I can do, because this CPU socket seems to've been made for the Athlon and nothing else. The recommended system requirements suggest a quad-core CPU, which I'd have to build a new computer for, and I kind of wonder how the game would make use of asynchronous threading. The AI isn't that complicated.

If I can fix this problem with a newer card, tell me what I want! I'd prefer to avoid spending more than $100 on this. My monitor goes up to 1900x1080 if that makes any difference.

posted by LogicalDash to Computers & Internet (8 answers total)

You have an old, old video card -- you want something with at least 1GB of RAM; the lack of texture memory is probably your (first) bottleneck. At $100, you're looking for a budget card, but a decent one. Something like this might work.

Your CPU is also very old. I suspect that's a significant part of your problem, but you won't be replacing your CPU and motherboard at your price point. However, you're rapidly approaching (or have reached) the point where modern games are going to start to choke on your hardware. A new video card will help, but if wishes were horses, you could ride it out for a bit longer with something like this, assuming that your motherboard has a PCI-E 2.0 slot.
posted by ellF at 7:01 AM on March 3, 2012

Response by poster: Why would the lack of texture memory cause problems with the lighting?
posted by LogicalDash at 7:25 AM on March 3, 2012

Lighting in most 3D applications (or at least, in Direct3D) is done by accumulating data in vertex buffers, and then handing those buffers off to the shader pipeline for whatever nifty things the designers want to do with them. If you're running a card where simply keeping the textures in memory is stuffing the card, things like lighting, transformations, etc. are going to be slow -- either because the card is swapping out to system memory (I suspect), or because it's just not able to perform the transformations quickly enough based on raw power.

The fact that anti-aliasing is causing problems is likely a function of card speed as well as memory, for the same reasons.
posted by ellF at 7:48 AM on March 3, 2012

Response by poster: No, the anti-aliasing is just fine. SSAO stands for Screen Space Ambient Occlusion. It's a shader, not a "real" lighting effect, so it's fairly useless without shadows on--I think?
posted by LogicalDash at 7:51 AM on March 3, 2012

Best answer: I have an HD 5670 and the game was giving me serious stuttering. I fixed it by resetting the 3D Settings in the Radeon Catalyst Control Center. That might be something you'll want to try. I don't think the graphic card is so bad that you'll have to run it in 800x600...
posted by Senza Volto at 8:05 AM on March 3, 2012

IAACGE, and the fact that the performance is tied to resolution, SSAO, and shadows specifically makes me think that the bottleneck is in the graphics card itself rather than the host machine / CPU. So you should be able to get some benefit by upgrading the card. It's difficult to say how much, because once you upgrade the card you might quickly bump into the limits of the host (right now, the possible CPU bottleneck is "hiding" behind the GPU bottleneck, so we can't see it).
posted by madmethods at 8:07 AM on March 3, 2012

Response by poster: Thanks, Senza! I had "Catalyst AI" enabled. With it disabled, the game goes up to 1280x800 with a fairly good framerate--it looks to be below 60fps, but for this game I don't need Quake levels of speed.

I'll hold off on the new video card for now, until the ones with >=3GB of VRAM get affordable.
posted by LogicalDash at 10:25 AM on March 3, 2012

You may have already done this, but a quick bit of generic advice - yeah, you have an older video card and your CPU is not the 454 police interceptor of microprocessors, but before you spend a lot of money on stuff check to see if you have the current drivers for everything. I've seen things go from unplayable to better than I could have hoped with a simple driver update.
posted by Kid Charlemagne at 11:18 AM on March 3, 2012 [1 favorite]