Hi, I'm getting an 890FX mobo in perhaps next week, and I'm wondering if I can run 8 GBS of ddr3-1600 ram at 8-8-8-24 timings with it still being 1600, and not 1333 or something?
If you're using a Phenom II X4 955 I'm pretty sure you won't be able to run 4x2 GBs of DDR3 1600 MHz RAM @ 8-8-8-24, only 1066 MHz or 1333 MHz. If you're using the Phenom II X6 CPUs that's different.
There's practically no noticeable difference between 1066 MHz and 1600 MHz except in benchmarks just so you know.
Another thing, let's say I get the ram to run at... 1333 at 8-8-8-24 with the 4gb, would I be able to run it at the same timing and mhz if I have 8 gb?
I'm concerned about the ram not being as effective if I increase to above 4gbs.
Not sure, it says 1333 MHz with one DIMM per channel - two modules only in this case. If you have 2x4 GB then that's possible, otherwise I'm not really sure.
Ultimately what I want to know is...
Will I receive better performance with 8gbs ram VS 4gbs (all 2gb sticks), or will the performance degrade if I increase from 4 to 8 or what?
If you need the extra RAM then there will be an improvement if you use 8 GB over 4 GB. Otherwise there's not much of a difference between 4 GB and 8 GB, you won't lose performance.