Running C4 RAM at C5 speeds -- Safe & relaible?

[craige]

I want to run C4 memory at Default... that will be @ 5-5-5, 1.8V...
So is this recommended & safe?

I dont want to run at C4 as i dont want high temps at 2.1V

PS: I have to buy C4 Ram, as C5 ram are out of stock at the moment of my favored brand.

[MadMan007]

That should not be a problem at all. In fact I'm willing to bet they will default to CAS5 and ~1.8V after installation for compatability reasons so you won't even have to do anything.

[craige]

Okay,

My preferred brand is Corsair and i was supposed to be buying this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16820145194

But this Gskill Ram is available as well where i live, but the only con according to me is it doesnt have Heatspreaders:
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231122

Also, as i want to run at default speeds... in Corsair i will get, 5-5-5-18 while Gskill has 5-5-5-15 -- Does it make any real world gaming difference

So which Ram will be best amongst two ?

[MadMan007]

In theory running different RAM at the same speed and timings should make no performance difference. As for the timings you can still set them to what you want in BIOS as long as the motherboard hs the option. As for real-world performance, it would be tiny if at all, also the first three numbers should add up to the third but chances are either set would run at 5-5-5-15. The G Skill does have heatspreaders just not a fancy heatsink like the Corsairs but it only matters a little for overclocking anyway. Get whichever is cheaper and available.

What motherboard and CPU are you using anyway, and will you overclock the CPU?

[craige]

I plan to overclock Cpu (Q9550) but very mildly, so i dont think i will even have to touch the RAM for overclocking...

[MadMan007]

If you get DDR2-800 it will be at or below spec up to 3.4GHz (8.5x400) CPU speed so you'll be fine.