If I buy a quad-core w/1066FSB what ram would I buy?

Planning on overclocking or just running the stock FSB?

It honestly depends on the motherboard/chipset these days. Some motherboards you can get by with buying cheaper rams (thus saving tons of money if you are building comps en masse), others are MUCH more particular about the ram they accept and will absolutely go apeshit on your ass if you don't get the right kind. OK, so maybe that is a bit of an exaggeration but they will simply not work depending on how picky the mobo is.

For example, the Asus P5N32-SLI Premium motherboard is the single *worst* motherboard I have ever dealt with when it comes to how picky it is to ram. Most OCZ sticks refused to work in it (ALL gold editions failed, I only got one 'platinum' version to work). OCZ managed to fix this problem by 'flashing' something onto the ram after I sent them into OCZ after reporting the problem. At the same time, the cheapest Corsair ram worked flawlessly with the board.

Then like ungratefulninja said, if you plan to OC you need to consider another whole set of 'rules' when looking for ram to buy.

General rule of thumb these days: Buy the fastest ram your board will support and that you can afford. Less than 2 gigs of ram these days is pretty much shooting yourself in the foot performance wise, if the board supports 4 gig, it is to your advantage to get 4 gig. Look at your budget, look at what the board supports, and do what you can.

As much as you can afford.

Really on the ocz? Im using 4GB of platinum and it works fine. Of course with 32bit its only seeing 3GB, but no problems that Ive found. My board vios version is 0204 and chipset is crush19. Does yours differ from mine a bit maybe?

Yep, nearly all the OCZ sticks I had to RMA and the guy I talked to on the phone said it was really common (he said he had just gotten off the phone with somebody who worked for ZZF, the guys at ZZF were getting pissed about the # of returns). Most of them that were incompatible were the 'Gold' edition sticks (including the 'camo' ones). I had some trouble with the plats as well but the newer rev. (revision 2) of the plats worked great, it was just the older plats that were not working. Bios version here is (updated) 0503. Tried reverting Bios to older builds as well but it didn't matter, it just didn't work with the non-flashed Gold sticks or the rev 1 plat sticks.

Guess I should run the bios update haha. They make it easy enough anyways.

I love how so fucking easy it is to update your bios these days, most of them you can do from Windows. And even if there is a problem while updating you can almost always revert by just pulling a jumper LOL. It's a far cry from just a few years ago that a fucked up bios update could really screw you over. Good stuff

Updated to 603, when I get back from vegas Ill see if I can squeeze a bit more out of it overclocked and see how stable it is now. Was a bit buggy when pushing it very far on the 204 bios. Not doing the others tonight, Ill let this one be the guinea pig. 7 more machines to update if this bios seems stable.

Thanks for the help guys. To answer some of your questions I will not be overclocking and the mobo I buy will be top of the line and use Nvidia's 680i chipset.

I ended up getting corsair:
4GB DDR2 XMS2-6400 UNBUF-240DIMM 4-4-4-12 EPP HTSK
My understanding is that it will run at 533 even though its 800 because my cpu is 1066. I could not find any ram at Dell with C3 timings. All of it was C4 and C5.

BTW most OCZ ram wants 2.2V instead of the 1.8v your mobo is set to as default. If you put the corsair in it to boot the system and change the voltage you culd probably put the OCZ in it. i read that last night. Don't hold me to it.