ram question (low latency, tccd etc) - pls look over system also

[LyNX31]

I was looking to build an a64 system to OC

there are 2 rams by PDP i was looking at from Jpeytons guide

PDP Dual Channel 184 Pin 1GB (512MBx2) DDR PC3200 Low Latency Retail ~$185
and
PDP Dual Channel 184 Pin 1GB (512MBx2) DDR PC3200 w/ XBL Retail ~$225

my goal is a stable overclock at ~2.4 ghz with an A64 3000+ winchester
and msi neo2 platinum and of course nice heatsink and fan

my question is this. can I achieve this with the low latency ram? What are the advantages of the PDP w/ XBL over the low latency ram?

any help is appreciated! thanks!

 

[jpeyton]

Not all RAM can be overclocked. Both types of memory you listed are rated at PC3200 (200MHz DDR). However, the one with XBL is a known overclocker, to 250MHz DDR and beyond.

A 3000+ Winchester has a 9X max multiplier. To reach 2.4GHz, you'll need to raise the bus speed to 267MHz (267x9=2400).

The low latency memory will probabaly not be able to overclock to 267MHz, so you'll have to use the memory clock ratio setting in your motherboard BIOS to lower the memory clock closer to 200MHz. The XBL will probably be able to hit 267MHz with relaxed timings, which will increase your memory bandwidth and overall system performance.

This is another good bet for memory: http://www.newegg.com/app/View...=20-141-194&depa=0

 

[LyNX31]

thanks jpeyton! great guide!

 

[jpeyton]

The 3200+ Winchester and the Patriot LL memory is a great combination; both have excellent price/performance ratios. The 10X multiplier on the 3200+ will give you a lot more flexibility when you're overclocking because you won't need high FSB to reach a good overclock, and you can use the RAM clock divider to keep the memory clocks around 200MHz DDR. It will still be a fast combination.

The great thing about Athlon 64s is that they have an on-die memory controller, so running the RAM in sync with the FSB isn't as much of an issue as with the older AthlonXPs. You'll still get great performance using a RAM clock divider.

 

[RussianSensation]

Let me throw another alternative:

Say you are going to get A64 3000+ @1.8 on socket 939 which costs $150
Now this XBL ram $225
Total Cost: $375

Now, mind you, you'd never run at 2-2-2-5 timings at anything beyond 225 with any of the above ram selections. In fact running 2.5-3-3-7 at 250:250 (1:1 ratio) will give you equal or maybe 2% better performance than if you ran 5:4 ratio and left ram at 200mhz 2-2-2-5.

Looser latency timings will somewhat offset the higher increase in memory speed. So the advantage (if any) of 250 mhz isnt as much as you think.

Now lets consider an alternative.

Geil 1GB PC3200 400MHz 2-64x64 Value Dual Channel DDR Memory 184Pin - $140
AMD Athlon 64 3500+ 512K 90nm (939) - $272
Total Price: $412

But in this case you are already at 2.2ghz and you'll be able to easily reach 2.6ghz. This alternative isn't as good from a price point though. I am just letting you know that often you don't have to buy the most expensive ram and sacrifice cpu speed, since starting with a higher cpu speed will probably guarantee higher overclocks. This 2nd option was especially attractive when A64 3500+ cost around $250 2 weeks ago (Total cost would have been $390). The thing is that during the holiday season, the retailers are raising prices since they know people will be buying right now.

But I am saying you can see how things can be changed. You can get A64 3200+ for instance and the $185 ram above and it'll be about the same price. In my eyes, sacrificing 2-3% performance due to timings is worth it if you can get 200 mhz in speed right off the bat. Of course in this case, I'd definately go with the cheaper 2-2-2-5 ram since I'd run at 200 2-2-2-5.

 

[LyNX31]

thanks for your input and insightful advice jpeyton and russiansensation. i think i will go with the 3200+ and the patriot low latency ram for (185)

 

[RussianSensation]

Originally posted by: LyNX31
thanks for your input and insightful advice jpeyton and russiansensation. i think i will go with the 3200+ and the patriot low latency ram for (185)

Let me know how $185 PDP ram overclocks, because I am thinking of picking it up myself.

Thanks.