Basic RAM Question

[Buggeroo]

I just put together a new comp with the following components:

ECS K7S5A motherboard (SiS 735 chipset)
Athlon XP 1800+
HIS GeForce2 MX 400 64MB
384 MB SDRAM

The reason I bought this particular motherboard is that it allows me to use either SD or DDR RAM and thus I could save the money for new RAM, while still being able to upgrade at a later time. What I would like to know is, if I replaced the 384 SD with 512 DDR, how big a difference in performance would I be looking at (I am thinking in the lines of 3D gaming)?

BTW, does anyone have any idea how much performance difference there would be between this board, with the SiS 735 chipset and a KT266A board?

 

[stuartd]

I think that the 'real' difference seem between SD and DDR is something like 10-20%

The difference in speed between the SIS and via chipsets is also about 10-20%

You might be able to find some reviews on Toms Hardware site to back this up.

 

[Krosus]

The only real @speed@ difference and i use the term loosely is minimal and pretty much unoticeable the whole buzz with ddr ram is the bandwidth the ram has is far superior to normal sdram. to be honest in 3d gaming you wont see a world of difference as most of the textures are loaded up into vid card ram when the game starts and wont touch system ram a whole lot except for loading screens.

If i were you dont bother with upgrading unless you feel like you have money to burn cause unless your machine is really slow on some games you may improve a few fps with ddr but nothing amazing.
a Video card with ddr ram is another thing alogether big difference.

 

[Buggeroo]

Thank you both for your replies. What you say Krosus complies pretty well with my own observations, from benchmarks and so forth. Looks like my next upgrade should be a DDR Video card

 

[cdogg]

The amount of speed difference you would notice using DDR instead of SDRAM depends on a number of things. 10-20% improvement might not seem like much, but that can easily translate to dozens of FPS.

In older CPU's (P-III's and pre-1GHz Athlons), using DDR might only result in a few extra FPS. In newer CPU's, especially like the one you have, need at least DDR RAM. You are severly bottlenecking your CPU if you decide to stick with SDRAM.

We're not just talking about your everday applications either folks. Even in gaming, it can make all the difference. If you had a video card with DDR RAM, but stuck with SDRAM for system memory, there will be a noticeable difference upgrading to DDR (in faster CPU's like Athlon XP's).

The video card accounts for roughly 4/5 of the rendering process. What about the other 1/5?? Do we forget that artificial intelligence, physical placement of each object, and some vertex details are all handled by the CPU. The information is then transferred from system RAM to the GPU on the video card where the rendering process is finished (lighting for each vertex and textures for each polygon).

Well, if you're bottlenecking your CPU and GPU with SDRAM, you get the picture...

 

[Buggeroo]

cdogg, you make some good points there. The reason i'm currently still using my old SDRAM is purely financial I had pretty limited funds to buy new components, so this seemed like the best buy for the money I had.
But since my video card uses SDRAM, wouldn't that severely limit the benefits of system DDR?

 

[cdogg]

Sure would. You're right in thinking that upgrading the video card to DDR would be the first move. Then as your budget permits, upgrade to DDR RAM eventually. You will notice a beneficial improvement in each upgrade!


~cdogg

 

[cdogg]

Also, the Geforce4 Ti 4200 128MB DDR is retailed out at around $199. The 64MB DDR version is only $179. If it falls within your budget, go with nothing else!!

Go here for a complete review and comparison:

http://www6.tomshardware.com/graphic/02q2/020409/index.html