DDR2 Ram Question

[Alien]

Originally Posted by Matth

IfAMDs operate differently, and will use a divisor that brings the memory to rated speed or as close as possible below, though some AMD clock speeds cannot deliver full memory speed due to the integer divisor limitations - AMDs on steps of 400MHz will run DDR2-800 at full speed, the inbetween steps will not.

Actually, it's related to the clock multiplier. [AMD] CPUs that have an even number for a multiplier [10, 12, 14] will run the memory at full speed, whereas those that have an odd number for a multiplier [e.g. my X2 6000, which is 15] will run a bit below full speed. You can get around this by just dropping the multiplier & upping the bus speed to reach the same CPU frequency as you had before [give or take a few hertz], but having tested it I can tell you there's little or no difference in performance. Then again, maybe the app I used didn't rely much on memory performance.

[boroboi]

You will find with dual channel RAM, that both DIMMS come with the same serial number. Thats because both need to be identical to eachother for a guaranteed dual channel setup. Using two unmatched DIMMS does sometimes work but not always a guaranteed outcome, which is why they are always supplied in pairs. You never see individual DIMMS for sale being advertised as dual-channel memory. All i can suggest in this case is they have a stock of single and matched DIMMS in stock.

Also you'll find with a lot of half decent boards, especially ASUS i believe, you can unlink the memory from the FSB, which eliminates the need to stick distinctly to memory dividers, however any half decent stick of RAM will tolerate having its timings tightened slightly at stock speeds, if his dont then its not the end of the world.

I've an excellent pair of Crucial Ballistix 1066 5-5-5-15, which i can easily overclock to 1230mhz. I can even take the clocks down to 1125 and tighten the timings to 4-4-4-12 which i do currently.

If hes going to be buying generic RAM, he probly isnt that much into tweaking his system anyway, but if they can supply matched DIMMS for that price then i say go for it

[zinglebarb]

I would not touch generic ram with a 20 foot pole

[boroboi]

I believe my feelings on generic RAM can also be discribed in perfect detail by Zingle

[bigboab5]

ok, I am getting there.. slowly but surely. So I want Matched pairs. Probably gonna go for the ones from the overclockers post that was up earlier. I am not into tweaking, but I cannot rule it out for future. So if I wanna get another 2 x 1gb at a later date do they have to be identical to the pair already in the computer? And what is the benefit of the pairs over normal generic sticks, apart from reliability?

Does these look ok as well link

[boroboi]

You can use two different brands fine, as long as they arent on the same channel.

So 2x1GB of Corsair for example would be fine with 2x1GB of OCZ in dual channel, they however must be the same speed obviously.

The benefit is you know you are getting two sticks that are identical to eachother, so they will definately work in dual channel.

[Matth]

Interesting... the "Team Elite" memory on Ebay does not seem to match any of their current packages, though the specification does seem to match "Elite".
http://www.teamgroup.com.tw/teamgrou...roductInfo.php

And not a great price for "off-brand" memory from an ebay trader.

http://www.aria.co.uk/SuperSpecials/...roductId=26802
If they don't sell out, that is some fast RAM ... 4-4-4-12 timings, but the voltage may be a problem, it's 2.1v, not 1.8-1.9v - typically, fast RAM does need more voltage.

[zinglebarb]

I would imagine if your slacken the latency you would get away with 1.9

[bigboab5]

Ok, you guys have helped me a lot, but what is all this latency stuff?

[Mr Angry]

Originally Posted by David F

I would imagine if your slacken the latency you would get away with 1.9

Exactly what I thought!! However, if you change the speed from 33rpm to 45rpm and put it in your Arcam 7se it makes your custard go cold and will impregnate the woman three doors down...or something, allegedly.

I had an episode lately whereby I attempted to install two twinned Corsair DDR2 PC2 6400 800mhz 512 sticks with two twinned Kingston DDR2 PC 6400 800mhz 1GB sticks on my Asus m2n32 sli - deluxe board (emphasis on deluxe, thank you) and it fried the living bejesus out of my board.

Currently a team of forensic RAM scientists are losing sleep somewhere in Taiwan.

It appears that "matched" means "matched".

[zinglebarb]

ooopps matey

---------- Post added at 07:00 ---------- Previous post was at 07:00 ----------

Originally Posted by bigboab5

Ok, you guys have helped me a lot, but what is all this latency stuff?

the 4 4 4 12 can be made 5 5 5 15 to over simplify

[bigboab5]

Hi guys....

right I know this has been a while, I was let down by my ebay seller re the original motherboard. So I now have a motherboard an ASUS PB5. While looking at what memory is required I noticed this..

Due to chipset limitation, DDR2-800 with CL=4 will be downgraded to run at DDR2-667 by default setting. If you want to operate with lower latency adjust memory memory timing manually

My question is, Do i make sure I buy CL=5 memory or do I get Cl=4? I can see plenty off each within my price range (£25-£35)

Thanks

Bigboab

[zinglebarb]

are you going to stick with that board long term? if so buy cas 5

[bigboab5]

Originally Posted by David F

are you going to stick with that board long term? if so buy cas 5

Yep, well for a couple of years anyway. So Cl=5 is what I want, thanks for that.

Boab

[zinglebarb]

Well in 2 years you will want DDR3 at least so yes