looking to double my ram

[whargoul]

i have the asus m4a87td evo motherboard. a phenom II 560BE unlocked to 4 cores. the auto over clock in the BIOS has the CPU @ 3.59GHZ with the bus speed at ~440MHz.

this is the RAM i have. http://www.newegg.com/Product/Product.aspx?item=N82E16820226103

i want to double it with something compatible that wont slow it down. i noticed it's latencies are listed as 7-9-7-24 which seems oddball to me.

any suggestions are greatly appreciated. thank you.

PS: not that i have any understanding of memory timings aside from what can be inferred from the definition of the word 'timings'

 

[Shockeray]

Really, exact timings don't make that much difference. 10-10-10-24, and 10-10-10-27 are really the same performance-wise, just incompatible.

The fist number in your RAM timing is your CAS Latency, or CL. It is the one that determines the speed that information can be retrieved from the RAM in clock cycles - of course, if you double your speed (800MHz to1600MHz) but half your CL (CL 6 to CL 12 [half speed is a number twice as big]) your RAM is going to retrieve information just as fast. But as your MHz goes up, you also get more bandwidth (not really sure why).

If you have a really stable 1600MHz RAM card and overclock it to 1866 or 2133, you have to bring the CL up so that it doesn't burn out your card, thus OCing RAM doesn't make it faster, it giver you more bandwidth.

Hope this helps.

Here is an 8Gb Blackline kit...
Mushkin Enhanced Blackline 2x4Gb 1600MHz CL8 ($75)

These are good, and not as expensive...
G.SKILL Ripjaws X Series 2x4Gb 1600MHz CL8 ($65)
G.SKILL Ripjaws Series 2x4Gb 1600MHz CL9 ($63)

But if you want the fastest 1600MHz, I would go with this one...
CORSAIR Vengeance 2x4Gb 1600MHz CL7 ($80)
(the improvement is going to barely be noticeable even in tests)

 

[whargoul]

thank you very much for the suggestions. i only have a cheap after market cooler. nothing too special, so i was lazy with the over clock and just click the auto OC in the BIOS. it puts my RAM at 1333 but OCs the FSB (or whatever the term is for AMD) so the ram is running at like 14xx somewhere around there (im at work right now) so i can't check. also, i'm sorry i should have mentioned i have 2 slots free. i think 12 gigs is probably overkill. and i had the idea that 4x2gbs would work better together than 2x2gb + 2x4gbs anyway. i came to that conclusion mostly on the idea that the timings would probably be different. no that i thought that would make them not work together at all. perhaps i'm over thinking it.

 

[whargoul]

when i go to newegg and search pc3 12800 DIMMS 2x2gb it's all 9-9-9-24 (i see one set that is 8-8-8-24). with the default of my current RAM being 7-9-7-24. i get the idea the BIOS will just choose the lowest common denominator and run all sticks @ 9-9-9-24 or 8-9-8-24. if my ram get's slowed down a smidge i dont suppose that is the end of the world, but i'd just like to think i made a more educated purchase.

 

[Shockeray]

Yes, your motherboard will try to get the lowest common number for your clock (actually the biggest number), but if a specific module isn't designed to run at that frequency it could either slowly burn it out, run with almost no performance, of just BIOS error and not start.

If your RAM has the same timings, you are always better to add as many cards as you have - the more Gb, the better - but if you want the most performance out of a specific Gb of RAM, you have to make sure you're actually running Dual Core, and make sure you have all your RAM running at max Hz and lowest CL.