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GDDR vs DDR

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March 13, 2008 6:30:53 AM

Been browsing the web for like ages, trying to find out what type of mem is better for gfx cards. I found the following about DDR3 and this about GDDR3 and of cause a ton of people who claimed that there was no difference, some people should really get the fact strait before shouting them out. While those two links where very informative they weren't exactly very conclusive. So I'm afraid, that unless you brilliant people can help me out, it seems I am forced to give up and admit myself beaten.

So I ask what is better for gfx cards GDDR3 or DDR3

More about : gddr ddr

a b } Memory
March 13, 2008 7:00:51 AM

RebornDK said:
Been browsing the web for like ages, trying to find out what type of mem is better for gfx cards. I found the following about DDR3 and this about GDDR3 and of cause a ton of people who claimed that there was no difference, some people should really get the fact strait before shouting them out. While those two links where very informative they weren't exactly very conclusive. So I'm afraid, that unless you brilliant people can help me out, it seems I am forced to give up and admit myself beaten.

So I ask what is better for gfx cards GDDR3 or DDR3


The G stands for 'graphics', as in memory developed for graphics cards or GDDR3. DDR3 is the general reference to system memory, as in memory developed specifically for your MB chipset, as in PC1600 DDR3. As far as you setting the facts straight, "How can I miss you when you won't go away." :sol: 
March 13, 2008 7:09:49 AM

Thx for your quick reply :) 

Yeah I got the part about G standing for graphic as well, but that wasn't what I was asking m8 ;) 

GFX card are produced both with GDDR3 and DDR3 so I gues what I am looking for is the pro's and con's of the two, before I wander out there and spend my hard earned cash on my new GFX cards. :) 
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March 13, 2008 9:47:10 AM

Out of curiosity I went through the egg and found all video cards with DDR rather than GDDR. None of which are up to date except for the non gaming type.

You should concern yourself less with the memory and more with the stats, you'll find that all modern decent cards that are worth the money and have good framerates in tests run GDDR3, and I think ATI even has some cards with GDDR4, but I haven't researched that so don't quote me.
March 13, 2008 12:49:44 PM

hmm you might be right since noone actulay seems to know whats best. :) 
March 13, 2008 1:06:44 PM

If I remember correctly, no graphics cards are created with DDR3, it's all GDDR3 but is often labelled wrong on the websites selling them. If you checked every manufacturer site, rather than websites selling them, I'm pretty sure you'll allways see GDDR3.

Anyway, GDDR3 is designed specifically for graphics cards (and graphics cards in turn are designed only to use GDDRx) and would probably be better than DDR3 when used on one. DDR3 would probably kick GDDR3's butt as system memory though, but I don't think it has been used as system memory except in the PS3.

Don't quote me on any of that though as I'm probably making it all up. :p 
March 13, 2008 2:10:00 PM

I remember reading about the GDDR versus DDR series a few years ago, and the most significant improvement of GDDR over DDR was:

1. You can activate a memory bank and issue a read request in the same clock cycle. In DDR they are each lagged by 1 clock because there is a collision.

2. In GDDR you can write and read the same memory location at the same time. This isn't as useful anymore because GPU cache is much improved over the 'old days' and you 'shouldn't' have to read the same location you are writing.

I tried doing a quick google search and I could only confirm #1, so #2 might not be correct but I couldn't find anything saying #2 isn't possible.
March 14, 2008 4:45:41 AM

mothhive well acording to several producers your wrong, heres one example: Click me
On another note it's realy astonishing that it doesn't seem that theres a single person or website out there who has looked into this :) 
March 14, 2008 8:17:02 AM

This DDR and GDDR is really strange for me.

The first HD3870 came with GDDR4 with mem speed around 2.25 GHz (1.12 actual). This means that it's faster than any DDR3 memory in the market.

The HD3870 was sold at around 200USD with 512MB GDDR4. How much the price of the fastest 1GB DDR3? It's still more than 200USD. Just checked at newegg, Kingston HyperX 2GB (2 x 1GB) 240-Pin DDR3 SDRAM DDR3 1625 (PC3 13000), is priced at 409 USD. It's 2GB, it means that for 512MB we have to pay for 409/4 = ~102USD.

Now, what is the price of GDDR4 512MB if the HD3870 sold at 200USD. Around 100$? Assuming that for the GPU itself (all part minus memory) took 100$. GDDR4 (2.2GHz) >> DDR3 1625 (1.62GHz).

I'm aware that GDDR has a different arhitecture with DDR. But if something can be applied in video card, than why can't it be applied for computer memory? If that happened, then we supposed to have faster and cheaper memory by now.

really strange to me ...

Maybe there are some good reason behind it, but I smell some corporate marketing technique :D 
March 14, 2008 8:38:31 AM

DDR can make one read or one write operation at one time.
GDDR can make both.
For example: While getting the data from computer's main memory for the next frame, GPU can access the memory and do the operations about the current frame.

If it was standard DDR, either GPU or PCI-Express should wait in order to get exclusive access to framebuffer memory.

This way with the same speed GDDR memory can act 2 times faster.

[Edit: Sorry guys, misinformation. It was VRAM. Not GDDR...]
March 14, 2008 10:12:34 AM

Maybe it has something to do with the fact that a GPU is a parallel processor, and a cpu isnt? Think about it
March 15, 2008 6:58:04 AM

I realy wish that Toms Hardware would make an article on this subject so relative hardware n00bs like me could feel more inlightened on this perticular subject.
April 14, 2011 5:34:22 PM

Ive had this question for a long time and this is the most i could get out of it. most people confuse ddr3 vram with ddr3 system ram (completely different) so they think that ddr3 is slower/shared and gddr3 is just dedicated. but ddr3 vram and gddr3 is usually where the memory is located and a ddr3 card is usually made for a specific computer so the memory is already somewhere on it, and the gddr3 memory is directly on the gpu itself, so gddr3 can just run a little bit cooler so it can be clocked a little more. therefor gddr3 is a little bit faster/cooler.
September 9, 2011 3:11:39 AM

antas said:
This DDR and GDDR is really strange for me.

The first HD3870 came with GDDR4 with mem speed around 2.25 GHz (1.12 actual). This means that it's faster than any DDR3 memory in the market.

The HD3870 was sold at around 200USD with 512MB GDDR4. How much the price of the fastest 1GB DDR3? It's still more than 200USD. Just checked at newegg, Kingston HyperX 2GB (2 x 1GB) 240-Pin DDR3 SDRAM DDR3 1625 (PC3 13000), is priced at 409 USD. It's 2GB, it means that for 512MB we have to pay for 409/4 = ~102USD.

Now, what is the price of GDDR4 512MB if the HD3870 sold at 200USD. Around 100$? Assuming that for the GPU itself (all part minus memory) took 100$. GDDR4 (2.2GHz) >> DDR3 1625 (1.62GHz).

I'm aware that GDDR has a different arhitecture with DDR. But if something can be applied in video card, than why can't it be applied for computer memory? If that happened, then we supposed to have faster and cheaper memory by now.

really strange to me ...

Maybe there are some good reason behind it, but I smell some corporate marketing technique :D 


I dont know it all but it seems to me that the reason we use DDR3 instead of GDDR3 is because GDDR3 is ONLY FOR graphics. If I want to know what 2 +2 is and you give me a picture of a tree then something is wrong. It does a different job and is specialized to do polygon counting. It's kinda like saying "why don't companies just give me 10Gigs of L2 cache on my processor instead of just using 2Gigs of RAM. I would think that it must be cheaper and they would not sale alot of those type of cards or processors!
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