8800GS with 512MB of RAM?

Plyro109

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Aug 23, 2007
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My friend next to me was browsing the apple store, and I was commenting on the new iMacs when I noticed that the new 24-inch iMac comes with an 8800GS.... that has 512MB of RAM.

http://store.apple.com/1-800-MY-APP...a/wa/RSLID?nnmm=browse&node=home/desktop/imac

I thought that RAM had to be linked with the Bus width (Please correct me if I'm wrong here.), and I know the GS runs with a 192-bit memory bus, and that should end up with RAM amounts at 384MB. I SUPPOSE it could be 576MB of RAM, but it still seems odd to round down to a specific 512MB.

Any thoughts on this?
 

crusoe74

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Just a quick glance at the internet for GF8800 for Apple and they all say 8800GT, I guess it's a typo on apple's website.
 

Plyro109

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Well, they made the error in a multitude of places, then. o_O.

It was further down the page, and under the order form, too....
 

KyleSTL

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Typo. Either the GPU is wrong, or the ram amount (or both for that matter). BTW, what ever happened to the 768MB 8800GSs we heard about when this castrated G92 was leaked? Was it just a rumor? Or did nVidia decide it would kill a lot of sales for higher margin 9600GTs and 8800GTs (which it undoubtedly would)? C'mon Palit, if the 9600GT and 8800GT can have 1GB, why can't this poor thing get 0.75GB?
 

crusoe74

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Exactly.

They're giving the tired old 8600GT 1Gb for chrissakes!!
 

KyleSTL

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And the 8500GT, yeesh!

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=40000048+1068320729&Configurator=&Subcategory=48&description=8500GT&Ntk=&srchInDesc=

Edit: And it's DDR2! You think there's a surplus of these chips?!?
 

LukeBird

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Nope, almost right!
There is now an 8800GS option on the iMac, the 8800GT was available on the Mac Pro only (AFAIR).
Quite how the 8800GS can have 512mb of RAM is a bit odd, perhaps it is sharing system memory as well? Unlikely, I know, but I can't think of any other reason why it wouldn't be 384mb...
 

Alissa

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The 8800GT is the standard GPU in the Mac Pro. The iMac's 8800GS isn't actually a GS chip. Due to the physical constraits of the iMac design, and many of Apple's other designs, they use a higher spec chip and underclock it.

This is usually done for thermal and acoustic reasons. We have several iMac's around the office atm and it seems the aluminium case Apple make a huge hoo-ha about on their website also doubles as a big-ass heat sink. Even with the lower spec ATI options, they get pretty warm to the touch but they stay quiet.

The rumour mill is working overtime as to what is actually in the iMac, GPU wise. Some say it's a 8800GT, some a 8800M GTX/GTS, others have entirely different ideas. The only really known facts are:

1) It's got a 256-bit memory bus and 512MB of RAM, so it's not any 8800GS nVidia have ever owned up to manufacturing.

2) Historically, when Apple underclock a chip they tell you it's something else from the same manufacturer and product line with equivalent or very close performance to the final result.

3) Apple have previously used mobile components in their desktop systems, including GPUs.

"Overclocking" the GPU back to it's "original" specs can be done, but I wouldn't recommend it. It's dead simple to do in Windows with Boot Camp, but I don't know if/how to do it under OS X.