Xeon, first, there is no "Intel 3.2 Ghz i875P Processor". The 875P is just one of the motherboard chipsets the CPU can operate on.
Secondly, don't get 3.2ghz CPU. Get the 2.4
C P4. Not only is the 3.2ghz more than 3.5 times more, but the 2.4C will overclock in many cases to ~3400mhz. Now I can't say if this is the same in this instance; but a recent review compared the 2.4, 2.6, and 3.06 P4's (all HT and 800mhz bus) and the 2.4C was
FASTER because it enabled the overclocker faster FSB speeds, which is going to improve overall system performance. It also actually O'clocked MORE than the 2.6, and to within only a few mhz of the 3.06ghz! Clearly the 2.4C is the one to get in that case. I would think the 3.2ghz has the same limitations as the 3.06ghz (multiplier too high for good FSB o'clocks), and since it's over $600 and the 2.4C is only currently $166, that's a no brainer.
The best memory to get at no cost considered is the OCZ PC4000
if you're going to overclock. If you are not, the OCZ PC3700 GOLD was the
fastest memory tested
at DDR500 speeds, even faster than top PC4000 brands. Since these modules are VERY expensive, the best best is the Geil PC4000 Ultra Platinum which came in 2nd overall in the tests (above Corsair, Kingston,et al). It is only $152 (2x256) while the OCZ PC3700 is about $220 and OCZ PC4000 is about $230. I can't see paying about ~$70 or more for only a few benchmark points. The Geil PC4000 was even faster in some tests, but overall the OCZ 4000 was faster. They not only overclocked more, but also had the fastest timings. The Corsair was a bit down on the list and CAS3. OCZ4000 is CAS 2.5 as is the Geil. OCZ3700 is CAS2. See one review
here for more info.
In a nutshell, all you need to know is the lower the memory timings, the better. In short, 2-2-2-5 is great. The first # is the CAS setting and is usually the most important. These settings can be changed in the mobo's BIOS. Faster memory has SLOWER timings. So, you want the fastest mhz memory you can get, with the lowest timings. There are many arguments here on what is more important: timings or FSB speed, but most tests show on Intel platforms that the bandwidth (FSB speed) takes more precedence over timings in most cases. On good memory, timings can usually be lowered more than their specs. Since I don't yet have a dual channel 867/875 mobo, I tried my 2x256mb Geil Ultra Platinum PC4000 for the hell of it on my Asus P4B533. The Geil is rated at 2.5-3-3-7 (which is the fastest I've seen on PC4000 memory, same as the OCZ PC4000). I have a 1.8a CPU and was able to get it to 2.4ghz on this mobo with my old PC2700 512mb stick. I put the Geil on and DEFAULT timings and it was SLOWER. I was actually able to set the Geil timings to 2-2-2-5 (which is what they were for the old PC2700 stick) and it was then slightly faster in most tests than the old stick RUNNING AT THE SAME SPEEDS. Then I was able to O'clock more to 140mhz FSB (25xxMhz) with the Geil which then gave MUCH faster bench's than the old stick. Now I know this is not DDR500 speeds, but still it's pretty good to be able to run DDR500 (PC4000) memory at those incredibly tight timings.
Another thing to consider with memory (and in the P4C800-E Deluxe) is Double Sided Vs. Single-Side modules. Double sided are going to give you more bandwidth and faster performance......
GENERALLY. I say generally because in the case of the P4C800-E Deluxe, IT TURNS OFF PAT in the BIOS when 4 DS modules are used! Yet, you can enable PAT with 4 SS modules making the latter faster in this case! I was going to send back or sell my Geil memory since I thought they were DS modules, but the 2x256mb DC kit is NOT. NOW after seeing this about no PAT w/4 DS modules and that being slower than 4 SS modules with PAT, I think I'm keeping them since I've pretty much decided on this mobo. (Since I'll probably eventually get another 2x256 sticks).
Here is the article on that. If any of your ARE running FOUR DS memory modules on this mobo WITH PAT ACTIVATED, please let us know the details.
DDR400/PC3200 is the highest listed in manuals because that is the fastest speed NOT OVERCLOCKED. That is the default speeds for an 800mhz FSB CPU (which is really 200mhz bus, as is DDR400 really operates at 200mhz since it's "DOUBLE DATA Rate"). Most good PC3200 will overclock a good bit more, but for the most performance, you'd need some faster memory; PC3700-4000. (DDR500 is also "halved", and runs at 250mhz). Since a 2.4C is a 12x multiplier (12x200 is 2400), when you bump the FSB to 250mhz (DDR500 memory or really good DDR400 memory possibly) this is going to give you 3000mhz. These are 1:1 CPU:memory ratio of course, which is a whole other story.
For your HD's.......the Raptors are a bit faster, especially at RAID 0. You're best bet would use 2 of them in RAID 0 0n the ICH5R controller, then get a WD800JB or WD2500JB for storage. Put your OS, swap file, program files, on the Raptors and on different partitions, then put your downloads, backups, storage, maybe the OE storage folder, on the WDxxxxJB drive.
I can't say about video cards, I'm in the same boat there as you.
HTH.