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zul277 · Feb 4, 2006, 10:52 AM

The question is, what is the real world performance difference between 128Mb and 256MB Video RAM? Been searching the forums for the answer to this question. I want to get the new 20" intel imac, but the only local Apple shop here only has the 128MB video ram in stock. There is a 1 week special for educators starting on monday, so I have only a few days to decide if I want to get a smaller VRAM or get the 256MB VRAM.

I plan to use this for photoshop, video editing and as a TV for my bedroom

I will also use iWeb for my blog, may get .Mac account for that. I will also convert my DVDs for my ipod.

[edit] By the way I forgot to mention that I may not get the special discount if I order the 256VRAM and will have to wait 3 weeks for delivery. I wish there was a way to order iMac from other countried

Weezer · Feb 4, 2006, 11:31 AM

People often overestimate the impact that vram has on real-world performance. If you don't plan to run off an additional high rez display, the 128 should be fine.

harrisjamieh · Feb 4, 2006, 12:58 PM

The 256 chips seem to be causing video problems in the new iMacs (see thread in iMac forum), and for that reason alone I would say go with the 128

baw · Feb 4, 2006, 03:47 PM

No problems with my 256MB upgrade.

mavherzog · Feb 4, 2006, 06:49 PM

Originally Posted by baw

No problems with my 256MB upgrade.

That's great to hear since the 20" iMac I have on order will have the 256MB upgrade. I've been sweating it out reading about the potential issues.

zul277 · Feb 4, 2006, 07:11 PM

I've also been reading about the problems, especially with frontrow, i will be using this a lot I think. I even saw a video of problem online.

I was thinking of putting a second monitor with the iMac but it's not that important because I may not even have the desk space to do so.

codex57 · Feb 4, 2006, 07:13 PM

My 256 doesn't have any problems either. Some 20" ones with 256 have problems, others don't. Apparently, me and baw don't have that problem.

I'm not quite sure if the extra VRAM is necessary for me, but I didn't have any special discount btw the two so I got the bigger RAM just in case.

JKT · Feb 5, 2006, 07:57 AM

Originally Posted by Weezer

People often overestimate the impact that vram has on real-world performance. If you don't plan to run off an additional high rez display, the 128 should be fine.

This may just be about true for current software (although if you plan on doing any serious image or video editing using Apple apps, Core Image and Core Video will make great use of the VRAM on your graphics card), however be aware that Apple is also moving toward using the GPU as a means of displaying the entire UI (Quartz 2D Extreme is already present in Tiger but is too buggy to be used full time). Then there is the concept of a resolution independent UI which is also on the horizon. More VRAM may be of some benefit further down the line in subsequent versions of OS X. How beneficial it is at the moment on a day-to-day basis will depend on how much you plan on using Core Image/Video aware apps and the filters that they provide. If the answer to that is a lot, then more VRAM is a given. If it is not very much then 128MB will be all you'll need. Naturally the other area where more VRAM will help out is gaming, but if you don't play games then it isn't much to worry about.

Photoshop will currently gain very little from VRAM as its filters and display are entirely (IIRC) CPU bound. It'll be interesting to see if that changes in future versions of the app - don't forget that Microsoft is moving in the same direction as Apple with Vista with its method for displaying the UI via the GPU. This could see Adobe and other imaging app developers shifting their software to make use of the GPU instead of the CPU in future versions.

For the original poster - I guess it depends more on how long you plan to have the machine. If it is 3 to 5 years or more, I would strongly consider getting the additional VRAM if you can afford it.

zul277 · Feb 5, 2006, 10:25 AM

Thanks for the informative reply JKT. I have never heard about plans to display the UI via the GPU. Have to read up on that. I guess I'll have to invest in the VRAM if I could as I do plan to keep the machine at least for 2 years (my current desktop is 5 years old and my laptop 3 years) It is time for an upgrade and time for a switch.

I think it would be easy if I could get the VRAM for an extra US75 or whatever it usually is. I think the shop is just using its monopoly of apple goods in my country to do whatever they want to vharge their customers.

badnewsblair · Feb 6, 2006, 09:04 AM

No problems with mine either. I think to say that there seem to be potential problems with the 256MB versions is a little premature and embellished, though it seems to be an issue for a few.

I guess the basic question is what will the user be using and how much he/she can afford. Just like standard RAM, there is no such thing as too much of it. However, if it is a question of more system RAM or more VRAM and you surf the net and write emails, then you need to go with the system RAM (obviously).

JKT · Feb 6, 2006, 10:30 AM

The 256MB VRAM issue appears to be software related - those suffering the issue have a later version of OS X installed than those that don't which has evidently introduced a bug in the video display. IOW, it is something that can be fixed by an update.