Is Dual Channel 333 enough for a 400mhz FSB?

[dguy6789]

I have 2 256MB sticks of PC2700 DDR memory, which is 333mhz. If i run it in dual channel mode, it is effectively 666mhz, correct? I have an athlon xp 2000 running at 333fsb right now. If i dropped the multiplier and increased fsb, would dual channel ddr333 be enough to FULLY support a 400mhz fsb? My mainboard is an ASUS A7N8X.

 

[infinite012]

Dual channel just means youre going to have a wider bus for the memory. Single channel (standard) memory is 64-bit, but dual channel is 128-bit. You're not getting any more speed, just a bigger tunnel. As for the 2700 running at 3200 speeds, it's pure luck.

 

[dguy6789]

ok, so even though it has more then enough memory bandwith, it is not fast enough to support 400fsb? I thought that since it had 5.4GB/s memory bandwith it would have more then enough to support 3.2GB/s mem bandwith which is what 400 fsb needs.

 

[pspada]

PC2100 = 266Mhz
PC2700 = 333Mhz
PC3200 = 400Mhz

If your ram is good enough, or you relax the timings, it may run at 400 - and then again, it may not.

 

[Bateluer]

For the Athlons, it does not really matter. Their FSB is not fast enough to take advantage of dual channel RAM. Unless you're using the IGP.

 

[Corporate Thug]

Originally posted by: Bateluer
For the Athlons, it does not really matter. Their FSB is not fast enough to take advantage of dual channel RAM. Unless you're using the IGP.

i agree

also, the ram may or may not hit 400 mhz. 34 mhz is a big OC for any ram

 

[jjyiz28]

Originally posted by: dguy6789
I have 2 256MB sticks of PC2700 DDR memory, which is 333mhz. If i run it in dual channel mode, it is effectively 666mhz, correct? I have an athlon xp 2000 running at 333fsb right now. If i dropped the multiplier and increased fsb, would dual channel ddr333 be enough to FULLY support a 400mhz fsb? My mainboard is an ASUS A7N8X.

from best to worst, lets say ur running a 400mhz fsb athlon

dual channel ddr400
single channel ddr400
dual channel not ddr 400 (ie 450, 333, etc..) async
single channel not ddr 400 async

search gamepc.com, under mainboards, nforce i believe
running dual channel async is still better than single channel async

 

[pspada]

I am ^. 3000+ @ 11.5x200fsb, 1.5 gig of PC3200, dual channel mode. 400Mhz across the board.

 

[dguy6789]

ok well, i tried running at 400 mhz accross the system, but even at really relaxed timing (like 3 5 5 7, or something) it wont make it, so i will be running my athlon xp 2000 at 333fsb untill i swap this ram out with 2 512 sticks of pc3200, thanks for all the help.

 

[pspada]

Realize that it's not necessarily your RAM that is not allowing you to run at 400Mhz. Your chip, as well as your motherboard has to be able to handle it. And with a chip with a 133fsb like your 2000+, you should consider yourself well off having it run at a 166fsb. When you migrate to a Barton or other cpu that runs at 166 default, you are more likely to be able to run it at 200fsb, assuming your current memory can, or you've replaced it with some PC3200.

 

[dguy6789]

I have an A7N8X rev 1.06, and with bios 1004, it officially supports 400FSB. the cpu should hit 400 fsb as long as i drop the multi plier to keep it near 1.67ghz.

 

[pspada]

But it remains to be seen if your chip can hit 400. Almost certainly not at stock voltage.

 

[infinite012]

Originally posted by: dguy6789
I have an A7N8X rev 1.06, and with bios 1004, it officially supports 400FSB. the cpu should hit 400 fsb as long as i drop the multi plier to keep it near 1.67ghz.

You have a rev 1.06. There's your problem. Only rev 2.0 boards officially support 200MHz FSB with hardware (Crush 18D/nForce2 ultra 400). The rev 1.0x is hit or miss with 200MHz no matter what asus tells you. No BIOS revision will ever allow you to have a 100% chance of hitting 200MHz.

 

[junkyardDawg]

boot into your BIOS and set memory speed at 120%, this will run the fsb at 166(333) and your memory at 200. this should tell if it's the memory or something else holding you back