Need to help my Dad upgrade memory for Leopard

My Dad has a 1.8 GHz iMac G5 with 256 mb of memory. He wants to get Leopard so I'm trying to help him upgrade his memory so that it can run it. Is the bare minimum of 512 mb going to be enough for his computer for leopard? And would it be ok to mix a 1 GB stick with a 256 MB stick even though they're they're different sizes? How much ram should we get?

And, if anyone feels like it, could anyone point me in the direction of which ram we should get? I don't know much about ram and only have the manual to go by in terms of what's required.

Thanks for anyone's help and sorry for the multiple questions.

Much better if he upgraded to 1GB (bare minimum IMO) or more. Is this a 17 inch or 20 inch 1.8 GHz iMac G5? Other World Computing is a fine place to deal with: select the correct iMac model from this list and it should take you to a page that lists all the different RAM modules that are compatible with your dad's iMac.

You can mix ram, throw a 1gb stick in. It's not "recommended for optimum performance", but it'll be 4x better than what you have now either way.

OWC (Other World Computing - eshop.macsales.com) is who I've always heard has good RAM for Macs. Crucial also.

darn, headcase beat me.

Thanks for the replies. He has a 17-inch model...however I don't know if it's the "ambient light sensor" model or not. How do I find this? The exact date he bought it was December 31, 2005 if that helps...

How to identify your iMac.

Thanks a lot.

No problem. Glad I could help.

I found this on newegg, does anyone know if Mushkin is a good brand? Or should I go with this? Is OWC worth the extra $3?

I've had no-name RAM go bad on me and it's really no fun at all. OWC has a lifetime warranty on the brands they carry and they are great to deal with. I think that trying to save $3 on a RAM stick is well to put it really mildly not a terrific idea.

I've never heard of Munchkin RAM. Crucial, yes. Kingston, yes. OWC's RAM too (I've used it). Techworks, yes. Samsung, yes. These are names you can trust.

Believe me when I say, don't try to skimp on RAM for $3.

Haha, ok thanks a lot for your help. That's all my questions.

Just to chime in... Mushkin is a reputable brand as well. With RAM the best thing to do is what MHC said... Get something with a lifetime warranty.

As far as brands go, OWC, Kingston, Crucial and Samsung are good, as MHC mentioned. I'd add OCZ, Patriot, Corsair and Mushkin to that list.

I had forgotten Corsair, I know that brand as well. Will try to remember Mushkin. My apologies.

Yep, Mushkin does make some good RAM.
Both chips you've linked to have lifetime warranties.
There wouldn't be any noticeable difference between OWC's house brand and this low end Mushkin stick.

If you happen to get one that goes bad down the road, it may be easier to get replaced with OWC than Mushkin, since you would be going right back to the place of purchase rather than going to the manufacturer and having to come up with receipt for proof of purchase. This would make it worth the extra $3.