FX Vs. Core i7: Exploring CPU Bottlenecks And AMD CrossFire

Can AMD's FX Keep Up With Its Radeon HD 7970?

When we talk about affordable hardware that performs well, we like to use phrases like "80% the performance for 60% the price." Those are always very honest numbers, since we make it a habit to measure performance, power, and efficiency. But they only capture the value of a single component, and components cannot operate on their own. 

After adding up the parts used in today's benchmark analysis, the Intel-based system crested $1,900, while the AMD platform ran us $1,724, both without cases, peripherals, or operating systems. If we wanted to call both setups "complete" solutions, we could add an $80 chassis to give us $1,984 and $1,804 machines, respectively. Since we're adding cost to both boxes, AMD's overall $180 cost savings becomes a smaller percentage of the total price tag. In other words, the other pieces that go into a nice high-end PC serve to diminish AMD's value leadership.

That leaves us with two completely biased ways to compare price to performance. We can only hope that pointing this out upfront keeps us transparent as we present the numbers.

An AMD bias would only include the price of the motherboard and CPU, maximizing value, like so:

A third alternative would allow us to talk about the motherboards and CPUs as upgrades, assuming you already have cases, power supplies, memory, and storage lying around. Of course, you probably don't have a pair of Radeon HD 7970s left over from some old machine, so the most balanced approach we can take at least takes processors, platforms, and graphics into consideration. Therefore, we're adding the $800 Tahiti-based duo to our shopping list.

The only way we can make AMD's FX-8350 look like a better gaming value than Intel's Core i7-3770K (specifically in the games and at the settings we used to test) is if the rest of the system is free. Because the rest of the system is never free, the FX-8350 never serves up better high-end gaming value.

From now on, we'll need to limit the use of AMD's flagship to systems already bottlenecked by their graphics cards. A less expensive CPU is more attractive when it isn't affecting performance negatively.

Intel Bias is in the (AMD) Cards?

Our benchmark results have long shown that ATI's graphics architectures are more dependent on a strong processor than Nvidia's. As a result, we usually arm our test beds with high-end Intel CPUs when it comes time to benchmark high-end GPUs, sidestepping platform issues that might adversely affect results designed to isolate graphics performance.

We were hoping that AMD's Piledriver update would break that trend, but even a handful of impressive advancements aren't enough to match the effectiveness of AMD's graphics team. Might Steamroller be the evolutionary step forward needed to unleash the GCN architecture's peak performance?

Thomas Soderstrom
Thomas Soderstrom is a Senior Staff Editor at Tom's Hardware US. He tests and reviews cases, cooling, memory and motherboards.
  • A Bad Day
    We were hoping that AMD's Piledriver update would break that trend, but even a handful of impressive advancements aren't enough to match the effectiveness of AMD's graphics team. Might Steamroller be the evolutionary step forward needed to unleash the GCN architecture's peak performance?

    I disagree. What's needed is even stronger push on the developers to use more than four cores, effectively, not some 100% load on one core and 10% on the other five cores.
    Reply
  • acktionhank
    Great article and very informative. The FX-8350 really held it's own until it came down to Skyrim.

    A Bad DayI disagree. What's needed is even stronger push on the developers to use more than four cores, effectively, not some 100% load on one core and 10% on the other five cores.
    I thought more cores were for multi-tasking, as in having multiple programs running simultaneously. It would suck to turn on BF3 and everything else running on my PC simply shut down because the CPU is under 100% utilization. How would i be able to play BF3 while streaming/playing some HD content on my TV that's hooked up to my same computer.


    Reply
  • alidan
    acktionhankGreat article and very informative. The FX-8350 really held it's own until it came down to Skyrim.I thought more cores were for multi-tasking, as in having multiple programs running simultaneously. It would suck to turn on BF3 and everything else running on my PC simply shut down because the CPU is under 100% utilization. How would i be able to play BF3 while streaming/playing some HD content on my TV that's hooked up to my same computer.
    single core performance... look up some other benchmarks, where they use itunes to encode things, or when i believe winzip went from single core to multicore, it shows a GREAT difference more cores can do to performance.

    the problem is that few games and few programs really scale, sure, pro applications almost always take advantage of whatever you put in them, but consumer, different story.

    more cores can offer more multitasking, but they also allow the load to be shifted from one core to all 4 cores and get over all more performance when properly coded.
    Reply
  • Someone Somewhere
    Personally I'd like to see the i5-3570K included in here. It's closer in price to the 8350, but should perform more like the 3770K (as the games are unlikely to use more than 4 threads).
    Reply
  • Crashman
    A Bad DayI disagree. What's needed is even stronger push on the developers to use more than four cores, effectively, not some 100% load on one core and 10% on the other five cores.I'm calling BS on this one because AMD's "eight cores" are actually four modules, on four front ends, with four FP units. Games have historically been limited by FP units specifically and front ends in general, no? What I'm seeing is that Intel's per-core IPC appears to be a little higher, when two different FOUR "full" CORE processors are compared.
    Reply
  • esrever
    There should be an i5 included just so you can have a middle ground.
    Reply
  • amuffin
    I'm really liking the new logo!
    Reply
  • de5_Roy
    like the article.
    woulda liked to see how a 3570k does against the fx8350 running the same cfx setup. impo, the price/perf woulda tipped further in favor of intel in configs like this.
    lastly, woulda liked some newer games like sleeping dogs, far cry3, max payne 3 in the benches instead of the ol' bf3 single player. i hear bf3 sp doesn't stress cpus that much. may be bf3 skewed the benches in favor of amd as much as skyrim favored intel. :whistle:
    Reply
  • quark004
    all these benchmarks are manipulated. First, there is this site which claims the 7900 series does well even with mid level cpus in gaming scenarios. And now toms claim a high end cpu. There is some propoganda here.
    Reply
  • abbadon_34
    It would be nice to see prices for components similar the SMB. Not because I can't look them up, but because the article is very price/performance oriented
    Reply