Take the 2-minute tour ×
Arqade is a question and answer site for passionate videogamers on all platforms. It's 100% free, no registration required.

If I have budget for one of two graphics cards as an upgrade, where one has more RAM but the other a faster clock speed on the GPU, which would have the biggest impact on gaming performance? The one with more RAM, or the "faster" one? All other factors should be considered equal (drivers, chipset, manufacturer, price, etc).

share|improve this question
1  
You have GPU vs RAM in the question, however (and this depends on the game) a fast hard drive - RAID 0 SATA or SSD - is equally as important if you want maps to load quickly. –  Chris S Jul 14 '10 at 22:23
    
@chris absolutely correct. I switched playing games off my 500gb harddrive, because I need my 160gb for time machine. The drop in performance is astounding, to the point that I'm considering getting a 64gb sd card for running games. The biggest performance boost I got was from upping the underclocked 9400m on my machine, but that's after I upped to 4gb ram. It's really hard to figure which piece made the biggest difference. The rule of thumb I use is that your machine will run as well as the worst component will allow it to. –  Mechko Jul 19 '10 at 5:26
    
possible duplicate of Determining if a game is CPU- or GPU-limited –  Zommuter Jul 31 '13 at 6:28
1  
WHAT? The other question is flagged as a duplicate of this one! –  CyberSkull Jul 31 '13 at 10:08
3  
This isn't a duplicate. –  Timtech Aug 16 '13 at 17:09

3 Answers 3

up vote 13 down vote accepted

Both ;)

You need RAM to hold the data - polygons, textures etc. More ram will allow you to show more detailed textures and run at higher resolutions.

You need a good GPU to do all the calculations needed for a modern game - lighting, physics etc. The better the GPU the more of these calculations you can do so you'll get better effects and it will have an impact on the resolution too.

Check the specs of those cards and then you need to decide what's important - resolution, effects etc. and go for the card that's better at those things.

share|improve this answer
2  
I would also add that, for the GPU, speed is not the sole criteria you need to look at. I'm not sure why the manufacturers make this so hard to figure out, but for example an nVidia GTX and GS are extremely far apart in performance even if running at the same core speed. –  GalacticCowboy Jul 19 '10 at 17:42
    
@GalacticCowboy It seems worth elaborating on why a GTX and GS might be so far apart despite the same core speed. As a GPU must process vast amounts of information in parallel (every single pixel demands personal attention), the two most significant attributes are stream processors (number of cores) and memory bandwidth (actual throughput in bytes). The basic difference between the GS and GTX, despite being the same model, is the active processor count. –  bpcookson Aug 27 '13 at 2:56

The real answer is neither.

Let me explain:

A high GPU clock speed means nothing, especially when you are comparing against brands. It is not on how many clocks per second a core runs at but rather how efficient the core is. For example, a GTX Titan has a core clock of 836MHz whereas the HD7770 has a core speed of 1000-1100GHz, so based on clock speed, the HD7770 is clearly better right?

Wrong. The Titan is actually 4-6 times better than the HD7770 because its core is more efficient. You will have to look at gaming benchmarks to figure out which card is superior in terms of the GPU core itself.

Next is the RAM. Pure RAM numbers tell you absolutely nothing about how a card will perform. A large amount of RAM will not always help you play games at higher resolutions, especially when a large amount of RAM is paired up with a really inefficient GPU (notice I didn't say low clocked GPU). Only powerful and efficient GPUs will be able to take advantage of 3Gb-6Gb of memory in a card.

Just like a computer, a card can bottleneck. An HD7770 with 2 Gb of RAM is a huge waste because the GPU core cannot handle 2Gb of data at a time while a Titan with 6Gb will be able to use all of that memory because its core is able to handle 6 gigs the textures and data.

This brings me to the last topic mentioned, high resolution. More memory will not help you play games at higher resolutions but rather, are a component that can. Like I said before, you need a very good graphics core paired with large memory in order to get the best experience. The memory must also have a large bus. 2 gigs of RAM in an HD7770 is a massive waste not only because of its slow GPU, but also because of its 128-bit bus. You have to have a wide bus in order to have more memory flow between the RAM and the core. The 6 gigs in a Titan can travel in a 384-bit bus, which is more than sufficient in transferring data between the core and the memory.

Final Tip: When shopping for a GPU, compare cards based on gaming benchmarks and not hardware specifications (except for the memory bus size ;)).

The best resources that I use when comparing GPUs are hwCompare and Passmark

share|improve this answer

Having a big amount of RAM could help when playing at big resolutions, let me say 1920x1080 and more.

For resolutions like 1680x1050 or less 1GB would be great but even 512MB is enough for most of games event at the highest texture detail setting.

If your monitor is 1680x1050 or less and the video card you choose has already 1GB I would suggest you to go for faster clock speed otherwise take the one with 1.5GB or 2GB of RAM.

ps. Clock frequencies can be overclocked, RAM amount cannot be increased ;)

share|improve this answer
1  
This is helpful for people who use a performance CRT for gaming, as they don't need to stick to a high native res to get a sharp image, so better "effects" (including AA and AF) are more important. –  MGOwen Jul 20 '10 at 6:39

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.