P4 & RDRAM speed

[StratonAce]

I've just put together my new P4 1.7 system using the Asus P4T motherboard and 2 512 MEG sticks of 800 RDRAM. It's running great except I see that in the initial bios boot screen it reports that my RDRAM is running at 400 mhz? I ran Sandra and Sandra reports the same (well, 401 mhz). Is this right? I thought the 800 in PC800 RDRAM meant that the memory runs at 800 mhz? Am I wrong here? In the bios menu I have 3 different options to set the memory to, either auto, 3x or 4x. Setting it at auto or 4x gives me 400, while setting it at 3x will show it at 300. I'm confused. Is the bios and Sandra actually showing me the bus speed? Which is 400 mhz, right? Someone please enlighten me.

Also, the newest version of the Asus P4T has hinged locking levers instead of the retaining clips to hold the heatsink/fan to the processor. Gods, did anyone else have a bitch of a time trying to get that sucker clamped down? lol. I'm using the Indigo Orb for my cooling so I'm not sure if other P4 heatsinks have this problem, but damn, I nearly had to lay on the sucker to get it clamped down. ;^)

Anyway, thanks in advance to anyone who can help me with the RDRAM speed question.

 

[StratonAce]

Oh, almost forgot, I'm using the 004 bios btw.

 

[BurntKooshie]

You're fine. Despite the funky name (Direct Rambus DRAM), RDRAM uses DDR technologies. It's 400mhz, but DDR, so it does 800Mega transfers/ second, which is the same throughput as 800mhz.

 

[shathal]

Yup, BurntKooshie got it in one.

RDRAM is double-pumped, like DDR - thus it's "actual" output is 2x "clocked" speed. It's like the P4 - that's advertised as 400 MHz FSB, whereas it's actually 100 MHz quad-pumped (i.e.: 100 MHz x4).

The end-result is the same.

Nothing to worry about .

Hope this puts your mind to rest .

 

[BurntKooshie]

Not to be too picky...but the end result's not the same. The latency for a true XXXMhz is lower than that of (XXX/2)Mhz * (2 transfers/clock). That is to say that 200Mhz has lower latency than 100Mhz DDR, but both have same throughput (but 100Mhz DDR is easier to get to, in most cases )

 

[StratonAce]

Yes, it does put my mind at rest. ;^) Thank you both Kooshie and shathal for your quick responses.

 

[Apex]

Weird, that's my computer too, except I have the older mechanism on my P4T.

I tried the Indigo Orb on the P4 1.7 (overclocked to 2006mhz), but I found it only made a 2-4 degrees F difference (matters how hard the CPU is working) over the retail heatsink, and made no stability difference, just a lot more noise.

What does your RAMBUS go to? My two 512MB RIMMS go to 944Mhz (472Mhz if you want to calculate it that way) with turbo enabled. Above that, they're flaky.

 

[BurntKooshie]

Apex - under what OS is this, and, is that under idle, or full load?

 

[Apex]

Win2k and during CPU Burn-In using Sandra.

 

[StratonAce]

Well, I ordered my 1.7 as OEM, so I don't have a retail heatsink to compare to. But the proc never gets above 42 degrees celcius, even under load. I played Giants last night for four hours straight and when I finally dropped out, my temp (thru MBM) was at 42 C. It should be noted that I'm using Win98 and I'm not overclocked yet.

As far as how far my RAMBUS will go, don't know yet, haven't tried pushing it yet.

 

[Texmaster]

<< I've just put together my new P4 1.7 system using the Asus P4T motherboard and 2 512 MEG sticks of 800 RDRAM. It's running great except I see that in the initial bios boot screen it reports that my RDRAM is running at 400 mhz? I ran Sandra and Sandra reports the same (well, 401 mhz). Is this right? I thought the 800 in PC800 RDRAM meant that the memory runs at 800 mhz? Am I wrong here? In the bios menu I have 3 different options to set the memory to, either auto, 3x or 4x. Setting it at auto or 4x gives me 400, while setting it at 3x will show it at 300. I'm confused. Is the bios and Sandra actually showing me the bus speed? Which is 400 mhz, right? Someone please enlighten me.

Also, the newest version of the Asus P4T has hinged locking levers instead of the retaining clips to hold the heatsink/fan to the processor. Gods, did anyone else have a bitch of a time trying to get that sucker clamped down? lol. I'm using the Indigo Orb for my cooling so I'm not sure if other P4 heatsinks have this problem, but damn, I nearly had to lay on the sucker to get it clamped down. ;^)

Anyway, thanks in advance to anyone who can help me with the RDRAM speed question. >>



Actually its reporting right at 400mhz.

I actually got rid of the clips in favor of &quot;the CORE&quot; heatsink.

Yeah the clips are a bitch and a half.

Couple of tricks if you are going to overclock.

#1 change the ram to 3x if you want to see how many mhz you can push out of it.
#2 watch those temps and remember to adjust your voltage accordingly.

Good luck!

 

[Texmaster]

<< Well, I ordered my 1.7 as OEM, so I don't have a retail heatsink to compare to. But the proc never gets above 42 degrees celcius, even under load. I played Giants last night for four hours straight and when I finally dropped out, my temp (thru MBM) was at 42 C. It should be noted that I'm using Win98 and I'm not overclocked yet.

As far as how far my RAMBUS will go, don't know yet, haven't tried pushing it yet. >>


Your rambus ram if you dont put it on 3x will hit 460-480 with very good cooling but probably no higher.

120-122fsb is usually max at 3x on the ram