What is important in a graphics card?

I have a four year old notebook with NVIDIA GeForce 9800M GTS. Unfortunately, heavy usage of the laptop means it is starting to fall apart physically, so I will have to start thinking about getting a new one in the near future. For the moment, the current one still works, so it is not urgent, but I do want to get a new one before rather than after it gives out.

When looking at new notebooks, one of the things I am considering is the graphics card. Most often, I use Wikipedia: Comparison of Nvidia graphics processing units - Wikipedia, the free encyclopedia. The problem is that I am not entirely sure which parameters are more important than others. Some of them have seen hardly any progress over the course of the four years since I got my current graphics card. These include bandwidth. 9800M GTS was at the lower end of the high-end mobile graphics card range. It has a 256-bit bus with 51.2 GB/s bandwidth, but even today only high end mobile graphics cards exceed that. The 600M/7000M series might finally change this - let's hope.... but so far, what gives? Why is this still near the top of the range after four years? Is it that bandwidth is not so important for performance, so graphics cards designers saw little need to increase it?

Texture and pixel fillrates have improved more than bandwidth, but again much less than I would have expected. Processing power (GFLOPS) is the one thing that seems to have seen the biggest improvement. I thought I could easily buy a mid-range mobile graphics card with my new laptop that would trounce my current one on every parameter, but now I am less sure. Than again, perhaps I am missing something, as I am not sure about the relative importance of these and other parameters for graphics performance and would really appreciate it if somebody would help elucidate the matter for me. Thanks!

 

You should get a nvidia gt650m or amd hd 7770m as they will be a good replacement. The new graphics cards midrange will beat the 9800m gtx easily. The 9800m gtx scors 4100 on vantage vs the 10000 or so for the 7770m or gt 650m.

 

The most important thing IMO is shaders and memory speed/bus width. Clocks and speeds are always adjusted to what the card can handle as long as you get GDDR5 and a 256bit Bus you should be able to game with maximum settings at 1080p.

Ultrabooks and smaller models normally come with GDDR3 64/128bit mid range normally come with GDDR5 128/192bit and high end GDDR5 and 256bit so it really depends what you are looking for. The new line up by Nvidia is looking tasty with the 640M for the smaller notebook 650M and 660M for the mid range and the 675/680M for the high end. Any of these will do the job it just depends on the size.

If you do intend to go for high end or desktop replacement you would do well to wait for the 7970M as it is about to slap Nvidia around the face when it drops.

 

The design of the GPU is massively more complicated than your approximation. Bus operations are energy/heat expensive operations, not ideal for laptops. GPU architectures have had huge design wins that haven't relied much on increasing memory bandwidth. The spec sheet doesn't give you good information if you are comparing different architectures. You might as well be comparing Ghz processor speeds between now and four years ago.

 

I think we easily forget how much the size and space constraints matter in a laptop. Look at how much more space, power and size a Desktop GPU needs then think how difficult this is for a laptop.

Having said that, the new 7970M is something of a trend breaker, it appears to have finished what the Nvidia GTX 485M started. If I was to buy a new laptop now, I wouldn't go for any less than a 7970M, after all, even if you don't need that level of power, why not leave your options open. Of course, this will also depend on budget, time etc.

A GTX 460M and / or a GTX 485M are still pretty decent replacements though. I expect you could get a good deal on the 6990M due to so many expected to be on sale due to the 7970M too.

 

As I have said, my purchase is not that urgent, so I am willing to wait until the 7000/600 series become available (as opposed to merely released). My budget for the new laptop is around 1,000 euros. The old notebook cost me about $1,500 (I bought it while I was in the U.S., but now I am back in Europe), so I want to spend a bit less (1,000 euros is about $1,300), while getting at least slightly better technical specifications. I figured this should be doable considering that four years has passed since I have bought the last laptop and that is usually quite a while in the computer industry.

Anyway, masterchef, if my approximation is an inaccurate measure of GPU performance (which it well might be - hence my asking about it here in the first place), could you suggest a better specifications sheet and suggest what technical variables (rather than just synthetic benchmarks) to look at?

 

For 1000 euro or £1000 over here you will not be looking to get the 7970M or 680M they will be much higher priced. My Clevo was 1500 euro just before the refresh with a 6990M. You really need to be in America to get the best deals and really dont want to be in the UK like me we get burned on VAT.

You might like to consider something like the MSI Force laptops as they go for around that price and will house the relabed 670M + and Ivy which is a good card sitting at the top of mid range and pushing high but comes with a 192bit bus width so its not go that little bit extra oompf. Still capable of the majority of games maxed.

 

Wikipedia is not a very good place to check tech specs, since the same shader numbers and clockspeeds can give vastly different results when you consider other variables. For a fairly accurate ranking of laptop GPUs, along with deeper information if you desire, go here. It's not perfect, but it's pretty good.

The best place to go for advice on a future laptop purchase is here. In this thread, you may have noticed that everyone's just naming their favorite mobile GPU re: performance, price/performance, performance/form factor, etc. In the "What Notebook Should I Buy" forum, people will actually consider your other needs when suggesting a laptop, such as budget, desired size, desired battery life, usage patterns, etc. Buying a laptop on the strength of a single component can leave you badly disappointed when you discover that it doesn't fit your other needs.

 

My mid-range laptop from November of 2010 will trounce your laptop on any given day. 9800M GTS (~9600GT) < GTX 460M (~GTS 450)

Also, the ending Memory Bandwidth matters more than the Bus Width used. Also, GDDR5 memory changed a lot. GDDR3 isn't used, except in lower level GPUs, these days. There are a few factors that one needs to be aware of when dealing with a GPU, laptop or desktop. The ROPs, TMUs, Shader count, and clock rates all come into play here too. You can't just say, "Oh well this GPU didn't increase it's pixel and texture fillrate all that much so I guess it's not that much more powerful..."

The GTX 460M is a rather weak GPU by today's standards with the GTX 570M/670M being the best mid-range performer. Doing a direct comparison between your 9800M GTS and my GTX 460M you'd see a sizable difference.

The 9800M GTS will score around 3700 points for a GPU score in Vantage. Compare that to the GTX 460M pulling 6700 points. That's with no tweaking at all. Mind you, the 460M likes to be overclocked and usually hits 800/1600/3000 pretty easily. That puts it around the level of a 5770 or greater. Easy win.

Again, Wikipedia is never a good place for technology info. Most of it is incorrect.

 

You are right that graphics performance is not the only issue I will be looking at when purchasing a new laptop. It is probably the one I understand the least, though, hence I wanted to clear up what technical specifications are good for judging it before considering other things.

GTX 460 seems like a high-end/middle-range borderline card, but you are right that it seems pretty impressive (even on the Wikipedia stats I used until now).

So, if ROPs, TMUs and Shader counts are important, where can I find reliable info on these for each graphics card?

 

Notebookcheck

For example:

NVIDIA GeForce GTX 460M - Notebookcheck.net Tech

 

Since modern real time 3d graphics is largely becoming shader limited, if you wanted a really vague look at performance variation over time, you could look at the core count ratios along with the core clock. That ignores a lot of other stuff, but if you *insist* on looking at a spec sheet and making an assessment about the technology solely from that spec sheet (which is a terrible idea all around, because good information about performance is *widely available* for GPUs), in the context of today's graphics, that is what I would look at.

That may not be relevant a few years from now, and it also doesn't work between Nvidia and AMD.

Of course, game benchmarks are far and away the superior method of determining performance, because game performance *defines* performance for consumer GPUs. Synthetic benchmarks are only relevant because proper game benchmarks that are ready for comparison can be hard to obtain. But they are available despite the potential testing difficulties.

 

Thanks, I will use notebookcheck.

Masterchef, I recognize that game benchmarks show a card's performance, but they do not show why this is so. I need to have a feeling of at least rudimentary understanding of how/why something is better than something else before I make a purchasing decision. I would not buy a car that got 5/5 stars in a review unless I knew the technical specifications of it either - and I am no car mechanic, but I need to have at least a very, very basic understanding of why it is technically better than another choice. That's just how my mind works - I can't help it.

 

then count the shader cores and multiply by the shader clock