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When comparing these Two PC builds, which would you recommend?

  1. Apr 18, 2010 #1
    The AMD "Katharine" computer

    Processor - AMD Phenom II X4 965 BE 185.99
    Motherboard - ASUS Crosshair III Formula AM3 socket motherboard $199.99
    RAM - Kingston HyperX 4GB 2x2 GB DDR3 1333 MHz $133.99
    Graphics card - Sapphire HD 5870 Vapor-X $439.99
    Power supply - Corsair HX850 $199.99
    Hard drive - WD caviar black 1TB 7200RPM 64MB cache $119.99
    Drive - LITE-ON 18x DVD-ROM - $19.99
    Operating system - Windows 7 Home Premium 64-bit $99.99
    Minus the cost of the case (I already own a coolermaster HAF 932 full tower case)
    +PC shop construction $99.99
    +Tax ???.??

    $1,649.91 (Approximately)

    __________________________________________________ ___________________________

    The Intel "Jessica" computer (considerably faster than AMD for only about $200 dollars more)

    Processor - Intel Core i7 930 $294.99
    Motherboard - Foxconn flamingblade LGA1366 $209.99
    RAM - G.Skill Ripjaws 6GB 3x2 GB DDR3 1600 MHz triple channel $179.99
    Graphics card - MSI Radeon HD 5870 $499.99
    Power supply - Corsair HX850 $199.99
    Hard drive - Western digital caviar black 1TB 7200RPM 64MB cache $119.99
    Operating system - Windows 7 home premium 64-bit $99.99
    Drive - LITE-ON 18x DVD-ROM $19.99
    Minus the cost of the case
    +PC store construction $99.99?
    +Tax ???.??

    $1,874.91 (Approximately)
  2. jcsd
  3. Apr 18, 2010 #2
    I take it this is a gaming machine?
  4. Apr 18, 2010 #3


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    The 1600mhz ram won't help with the core i7 cpu unless the motherboard can overclock the ram, otherwise the core i7 cpu is going to run the ram at 1066mhz, and if you select Kingston regular (not hyperx) 1066mhz ram, it will default to a faster timing for 1066mhz, 7-7-7-20.

    You might consider getting 2 500gb drives, using the 2nd drive for swap files and backups.

    I assume you have a LCD monitor. There's a problem with all HD5xxxx series cards that only allows 60hz refresh rate if resolution is a multiple of 16:9, but this is only an issue for CRT monitors. Why the MSI versus the Sapphire Vapor X?
    Last edited: Apr 18, 2010
  5. Apr 19, 2010 #4
    Sapphire discontinued the 1st revision of their HD 5870 Vapor-X. The 2nd revision runs about 13 *C hotter on both idle and load, and less efficiently. But it has a physically smaller PCB. The MSI HD 5870 Lightning has a massive copper heatsink, with two high-rpm fans. It also has a 900 MHz core stock clock speed, instead of the usual 850 MHz.

    This is off-topic, but is there any noticeable performance increase (particularly in gaming) with faster clocked memory?
  6. Apr 19, 2010 #5


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    The faster clocked memory only helps if the cas latency ends up taking a smaller amount of time. For example, 1300mhz memory at 8-8-8 would be 6.7% faster than 1066mhz 7-7-7 memory, assuming your motherboard allows you to select the higher voltage, and overclock the memory to 1300mhz with CL at 8-8-8. As mentioned, core i7 cpu's only support 1066mhz memory. I've read conflicting documents that the core i7 extreme cpu's support 1300mhz memory, I'm not sure how the motherboards overclock the ram interface. 1600mhz memory at 9-9-9 would be 16.7% faster than the 1066mhz memory. 1600mhz at 8-8-8-24 would be 31.3% faster.

    The effect of memory on a game will be less than the memory speed differences because of the cpu cache, and the fact that cpu and graphic processing are usually more significant overhead than memory access time for games.

    I'd recommend looking for performance benchmarks at http://www.tomshardware.com, and posting questions at the forums there. Crysis still seems to have the lowest frame rates of any game (except perhaps Flight Simulator X maxed out), it's not played much anymore, but it's still used for some benchmarks.
    Last edited: Apr 19, 2010
  7. Apr 19, 2010 #6
    Could you please confirm that claim with a link? I may be able to save a little bit of money buying 1033 MHz DDR3 if that's the case... Maybe spend that extra cash on an aftermarket CPU cooler.
  8. Apr 19, 2010 #7


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    Articles from Tom's Hardware:



    Then again, there's not much difference in the total price, even with 6GB. Would 3GB not be enough? I'm not sure what is needed for most of the newer games out there.
    Last edited: Apr 19, 2010
  9. Apr 20, 2010 #8
    For gaming, you'll see very little difference between the two builds. Hardly any games are coded to take advantage of the increased parallelisation afforded by the i7 CPU and triple channel memory has only marginal benefits in most applications. In fact, the i7s are often slower than the equivalent non-hyperthreaded CPUs in games. By the time most games are able to make use of the extra capabilities of the i7 setup the technology will have improved and fallen greatly in price so there's little sense in buying it to be 'future proof' either. The only real reason to get an i7 for gaming is if you're running multiple high-end graphics cards, but given the capabilities of a single 5870 that seems rather pointless. Of course, if you're also going to be using the computer for video editing/encoding then the i7 might be worth it (depends on how precious your time is... I'd take the slightly longer tea break and $200!).

    As for the memory, as the articles on tom's hardware show there's little benefit to be had from faster memory in gaming (obviously the GDDR5 sitting on the graphics card gets plenty of action, but standard RAM, less so). I'd go for Crucial's very capable basic ddr3 memory (code ct2kit25664ba1339) as recommended by tom's hardware http://www.tomshardware.co.uk/ddr3-4gb-p55,review-31728-6.html
    Setting the memory to the desired frequency/timings is very easy in the BIOS if you've got a decent motherboard, although the default for an i7 is 1066 mhz, I doubt many people run it at that speed... even if the desired frequency requires a mild overclock (I'm not sure of the memory multipliers available) it wouldn't be an issue.

    Finally, a couple of points about the components: the motherboard on the AMD build is vastly superior to the Foxconn in the intel- you should expect an X58 motherboard to be significantly more expensive than the alternatives, and an 850W power supply is overkill: a quality (eg. corsair) 550W would almost certainly be enough even if overclocking and even for two 5870s 750W would probably do.
  10. Apr 20, 2010 #9
    I may upgrade to an HD 5970 (dual-GPU PCB) in the future. The i7 is excellent with running multiple graphics cards. Someone on another forum told me about how they have a 3-way SLI GTX 285 system with absolutely ZERO bottleneck with their i7 running at only 3.4 GHz.

    The Phenom II X4 965 would halve the performance capabilities of 3 GTX 285's SLI due to severe bottlenecking.

    The only problems with the HD 5970 are high prices, high temperatures, and high fan speed and noise because of those temperatures.

    The 850W PSU would allow for future upgrades. Would 850W be enough for a single HD 5970?
  11. Apr 21, 2010 #10
    OK, if you're going for a multiple GPU setup then the i7 starts to make more sense. I wouldn't say the phenom would halve the performance of a 3 way crossfire, but there would be a noticeable difference. Overclocking also tends to be better in the i7s. Of course, AMD are releasing 6 core chips soon (expected to be around $200) that most probably won't cause any bottleneck, so it's still worth considering an AMD platform... they tend to offer the best performance for the money, despite intel having the clear lead in absolute performance.

    The power requirements of a 5970 are still not actually that high- 600W is recommended by AMD so a 750W power supply would give plenty of headroom even with overclocking (more importantly, you should be looking for a total of about 50 amps on the 12V rails, so something like the corsair tx 650W would be enough, I'd go 750 to be safe).

  12. Apr 22, 2010 #11
    I think I'll go with the Core i7. The Nehalem processors will last much longer in terms of being future-proof. Probably 3-4 years or longer, before it becomes laughably obsolete. Much longer than AMD's Deneb.
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