DDR2 vs. GDDR3 Graphics Memory

So we all know the new Inspiron and Vostro notebooks use DDR2 graphics memory. So...
What are the differences between these two?
Is it significant enough to the point where the use of these two differently designed cards gives obviously noticeable differences?
Do you think Dell would implement GDDR3 into their notebooks anytime soon?

 

Yes, the difference is very noticeable. The 8600GT with DDR2 is essentially two thirds as powerful as the ones with DDR3.(Compare benchmarks b/w the G1S and 1520). And knowing dell, they wouldn't include DDR3.

 

Though that's what benchmarking says.

In the end, it's about performance when gaming, and there the difference would be more about a boost in FPS and a bit more eye candy.

The DDR2 overclocked is the DDR3 stock pretty much.

 

Just to clear up some misinformation - GDDR3 is not intrinsically faster than GDDR2, merely that is can be clocked higher.

The 8400M GS seems to come with GDDR3, albeit clocked at 500MHz as opposed to 600MHz as was expected.

The 8600M GTs are equipped with GDDR2 running at 400MHz as opposed to the expected 700MHz GDDR3. It will make it quite a bit slower than the 700MHz memory clock version.

As for implementing the higher clock speed, it is due to both cost as well as thermal envelope. It's unlikely they'll implement it in the current version of the laptop, although it's possible they could modify the cooling system to accommodate a higher clocked card.

 

DDR3 uses less power and therefore generates less heat. GDDR3 runs at a much lower voltage than DDR2 leading to the heat problem. It runs at 2 or 1.8 volts depending on manufacturer. This would make it incredibly difficult to overclock DDR2 to gddr3 speeds. There are also several innate differences between ddr2 and gddr3. The bandwidth in GDDR3 is 4 bits of data per pin in 2 clock cycles. It also contains other alterations to better handle graphics demands. Also no current card utilizes GDDR2 only standard DDR2 or GDDR3. GDDR2 was not very efficient and generated a fair amount of heat. GDDR2 also still contained some crap left over from DDR ram.

The overclocked ddr2 has only reached 500mhz. That means that in memory intensive situation or perhaps at higher resolutions the GDDR3 would still perform better. The 3d mark results match the stock gddr3 card mainly because of the overclocked clock speed.

That being said DDR2 can still be overclocked, and the 8600gt is a descent card regardless. DDR2 also has some advantage in regard to latency, but I don’t think it matters in this application. I don’t know if the DDR2 in these cards are even configured to use their better latency. Plus, low latency isn’t as beneficial as people think. An intresting article on low latency can be found here http://techreport.com/etc/2005q4/mem-latency/index.x?pg=1.

Some of my information came from
http://www.lostcircuits.com/memory/ddr3/

 

More like 5/6ths the speed.

8600M with GDDR3 in a G1S gets around 3600 in 3dmark06
8600M with DDR2 in a Inspiron 1520 gets around 3000 in 3dmark96

 

Hi, this is my first post here. This is a nice forum, lots of good info here. I learned enough to order myself a vostro 1700 with the 8600m GT but i am confused as to how this card will perform.

Ive seen some people reporting that the site says GDDR3 but im sure ill be getting GDDR2 as thats the only type of memory mentioned on the site. Will it be faster than the 8600GS GDDR3?? Its got double the shaders but much less memory bandwidth according to wikipedia. Does GDDR2 really matter all that much?

 

I don’t think they make GDDR2 anymore as it was in-between ddr and ddr2. Cards that people claim use GDDR2 use standard ddr2, which is better anyways. The GT will be superior regardless of memory or speed. The 8600 gt is a powerful mid-range card in any configuration.

 

If you guys want to know the differences between GDDR2/GDDR3, I made a thread about it. Click Here for the thread.

 

You're correct. I was mistaken about GDDR2 - in fact it should be DDR2.

However, voltage for GDDR3 and DDR2 are both around 1.8-2.0V - GDDR3 has a few internal differences that make it a bit better suited for graphics implementations, and drops some old DDR baggage. These simplifications are the biggest contributors to the lower power consumption. As well, GDDR3 is based off DDR2. Both have prefetch buffers of 4 bits. The much higher frequencies possible with GDDR3 is attributable to on-die termination, which improves signal quality quite a lot.

 

I did make a mistake regarding the voltage. It certainly isn’t much less than standard ddr2 even if it uses less power. I was looking at the voltages for GDDR2 for some reason. I also have my desktop memory at 2.35V so I wasn’t thinking. Your also right in saying ddr2 is 4bit. However, both GDDR3 and DDR2 have on die termination only GDDR2 didn’t. Still the DDR2 in the 8600 is rather slow and can’t be clocked to GDDR3 speeds. I believe people have maxed it out at around 500mhz. Not all DDR2 are created equal and capable of reaching those speeds. Well, I learned something from this so I’ll give you a rep.

 

Same to you - for some reason I just assumed Dell was using GDDR2 - I wasn't completely aware than cards are in fact using mostly DDR2 and not GDDR2. I'll rep you when I get a chance, this forum software is designed so we can't cheat the system and rep each other.

 

If you are comparing stock to stock, then the scores are(from reviews from this site itself) 2906 for a 1520, vs 3814, for a G2S, which is essentially the same as a G1S. OCed scores would show much greater differences. For a really good read through the 8600M GT's capabilities, I recommend this thread.

 

Those scores you cant compare scores unless you state the resolution used. I got 3175 stock on my 8600gt with 1280 x 800 resolution

 

Another thing is that processors change the scores decently in 3DMark06, and as you can clearly see, the Asus has a better one... So until you compare two PCs with identical hardware, except one having DDR2 and one GDDR3, you can't really tell how much of a difference was made.

 

At 1280x1024, the GDDR3 gets 3800+ most of the time it seems.