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Matching CPU and graphics card

By DarrylJ
Oct 22, 2004
  1. I seem to be in the market for an upgrade on a regular basis and I have a question which recurs each time. How does one match a graphics card to a particular CPU (and motherboard)?

    For example, I know that it would be a waste to put the latest and greatest video card on a motherboard with an old 75MHz Pentium (assuming for a moment that the motherboard supported the new card).

    But where does one draw the line? Is there a particular test, or set of specifications, that can be used to determine the "maximum" video card that will work with a given CPU?

    My local store is not about to let me test one graphic card after another to find the best match for a box where I want better video performance. But I don't want to spend money on an upgraded video card if the CPU is already maxed out supporting the one that's already installed.

    What to do? :cool:

    I've done some searching around over the past few days and I cannot find anything that addresses this. I can't be the only one facing this kind of issue.... I see people making pronouncements about video cards with CPUs; do they know something I don't, or are they just providing reasonable guesses (or complete BS)?

    TIA,
    --
    Darryl
     
  2. MYOB

    MYOB TS Rookie Posts: 492

    TBH, theres no "matching" to do. Its not like the CPU can stop the card working fast, although obviously the motherboard can.

    I use an old video card and a relatively new CPU on my desktop because it spends most of its time crunching away. However my P200MMX has a 16MB Voodoo III/2000 in it because I want it to be able to actually play video and some mid 90's games OK.

    The board is the limiting factor - socket and bus wise.
     
  3. Greeno

    Greeno TS Rookie Posts: 281

    Agreed with MYOB...

    If it were me, I'd get well reviewed g/card, and try and help the things around it... Memory Size/Speed, CPU freq. etc to avoid bottlenecks this way, but there are no matched pairs for such things like MYOB said.

    I would certainly consider my budget, find a few cards that fit it well enough and google around for reviews, they'll tell you their test setups etc, if they're anything like your PC then bonus!
     
  4. DarrylJ

    DarrylJ TS Rookie Topic Starter

    I was under the impression that the CPU did the work to feed data to the graphics processor. If the CPU is too slow, the GPU will be sitting around waiting for more data to process and send to the display: a slow CPU will limit a video card to a percentage of its theoretical maximum.

    Is this no longer the case?

    Does the AGP (or newer video systems) work in isolation from the CPU? (Which would then put your answers into context for me. Yes, a faster GPU will produce faster output regardless of the CPU speed.)

    I appreciate the responses. (It's good to learn new stuff!)
    --
    Darryl
     
  5. jstillion

    jstillion TS Rookie Posts: 91

    The newer video cards are designed to help offload work from the CPU to have the GPU (video card) to do the work.

    It is correct that you can have an older system and a new video card where the CPU is holding up the video card potential (and you wasted money in something not beneficial).

    The main element is the game it self, a game will slam the cpu and the video card will off load as much as possible. It's the slowest component in your system that will affect game play. Be in your video card, [CPU, Memory, Mother Board] system speed, if you use 3D audio, what sound card you have if it's turned on, and at time your hard drive.

    My system is pretty fast but I have a old / slow hard drive. For me I would replace my hard drive 1st, then upgrade video card, then my cpu to increase my gaming performance. I'm currently happy with my system, can play Doom 3 / FFXI nicely.

    What computer cpu / mother board are you thinking of, we may be able to give you examples of what would be a good price / video card range that won't waste your money but give you good performance.
     
  6. DarrylJ

    DarrylJ TS Rookie Topic Starter

    Everyone keeps coming back to the currect specs of the computer I want to upgrade. OK. It's a 1200 Athlon CPU with an GeForce 2 MX400 video card. The motherboard is an Elite K7S5A with a 350 watt PS. 512 MB RAM. Windows 98SE.

    But if you are going to recommend a video card, how do you know that it is suitable, considering the other components?

    That is, after all, my main question. How do you determine the best match of video and CPU?

    Are recommendations based on trial and error? Personal experience? An analysis of the specifications....? If it's the specs, what are you looking for?

    I have other computers in the house. Eventually I will be upgrading them as well. Or replacing them with newer ones. If there is a method of analyzing CPU and Video card specs to get the best match, I'd love to know it.

    Maybe it is just trial and error, reading reviews and such. That's OK. I'm just looking an an answer of how one determines which video card is the best option for a given motherboard/CPU/PS.

    --
    Darryl
     
  7. MrGaribaldi

    MrGaribaldi TechSpot Ambassador Posts: 2,512

    The only truly general advice I can give on how to choose a new gpu is to figure out what you're going to use the computer for, and then research on the net which card is going to give you the best bang-for-buck with that (area) in mind.

    To expand it somewhat more:

    First you need to figure out what you are going to use the machine for.

    If it's just email & internet, stick with what you have, or get a Matrox card (due to their exceptional 2D).

    If it's to play older games, which games? And what GPU's where considered the best when they were new? Are any of those still on the market, if so, are they cheaper than newer cards? (Sometimes due to staying in-stock for so long they can cost a lot more than a better newer card). Important: Are there drivers for the card for your OS? Buying a Voodoo/3dfx based card when running XP requires a lot of work from you to get it to work properly, but will allow you to play older games using GLide.
    Note: Buying an older card only makes sense if you're going to play old games. Post here what games you are going to play for a suggestion if buying an old card is a good idea or not...


    If it's to play newer games, what kind of games? And what is your budget.
    Mostly the more ram the better (more on that later), but if you're buying a low-budget card with 256 mb it might actually be slower than the 128mb version. (If it's very cheap, the ram is cheap and can not run as fast as the 128mb version) This is not applicable for mid- to high-end.

    Also, make sure the card is running at a 256-bit bus and not a crippled 128-bit bus, as it'll degrade the performance of your card (even if you have an older setup)

    The reason I say get as much memory as possible is that it'll enable you to use a higher # of FSAA or better textures even though your cpu isn't able to feed it as much info as the card can handle.

    When you're CPU limited, you are able (to a certain extent) to increase certain visual settings, as they're fully processed on the GPU. FSAA and AF can often be increased one or two notches when you're cpu limited.

    Also, having a newer card means that when you upgrade your system the next time means it won't be too outdated for you to play newer games (though certain cards scale better than others).
     
  8. Phantasm66

    Phantasm66 TS Rookie Posts: 5,734   +7

    Buy the best things you can afford. If you have a limited budget, think about what you want the PC's main duties to be, and then spec accordingly.
     
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