4gb ram on macbook (2009 refresh) problems?

Just buy reputable RAM, and you'll be fine. The "issue" so to speak is just the macs being picky about the RAM being well made, partially because DDR3 is a new technology.

Crucial, OCZ for a couple, will be fine. Also, a quick forum search should turn up what people here have posted about this issue in the very recent past.

My has no issues.

Bought the Crucial RAM.

The white macbook early 2009 uses DDR2 ram, not DDR3. I think the problems were with the Unibody Macs and DDR3.

http://www.newegg.com/Product/Product.aspx?Item=N82E16820226019

I have this RAM and it works GREAT!

Read that are many having issues with OWC's RAM. I just recently bought 2x2GB from MacSales.com and kept my finger crossed while stress-testing it.

I ran memtest osx for 2 passes (an hour or so), techtool's ram test and use it for normal work for two days. It has no freeze or crashes so far.

It has micron chip and labels and I understand there are comments that OWC may ship different brands. Guess this 'luck' stays on.

I bought 4gb of Kingston RAM off Amazon and put it in my white macbook (2009) and have had no troubles at all. I think maybe you got some bad RAM.

The OP might be referring to those that bought the incorrect memory pc-6400 (800 mhz) instead of pc-5300 (667 mhz). It seems that when a 4GB kit was installed using the pc-6400s, the user had big problems but when they put in one of the chips alone or in combination with their old RAM it worked. Most of those effected corrected their problem by purchasing the correct RAM. The same problems would still effect the newest 2009 2.0GHz nVidia MacBooks. -GDF

I just got Crucial 4 GB kit. It has no problems.