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Old 2005-05-21, 01:48   #1
Longshot
 
Mar 2004
Somewhere downrange

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Default Learning About RAM the Hard Way

One of my computers is an AMD XP2700+. It had a 512 stick of PC 2700 RAM that developed a problem. It would no longer run at 166MHz. without getting hardwear failure warnings. I replaced it with 2 256MHz. PC3200 sticks of Crucial's Ballistix RAM...their high-performance stuff. Well, my iteration times increased from .154 to .172. The RAM ain't bad so i'm stuck with it. Tech support was no help. They telling me to raise my FSB to 200. That would cook the CPU I am sure.

If your system calls for PC 2700...use that. I am going to trade this RAM for a stick of Crucial's regular RAM to get my times back down. There is a lot to be said about leaving well enough alone. I will approach so-called high-speed high-dollar RAM with a tongue-in-cheek attitude from now on.
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Old 2005-05-21, 02:49   #2
sdbardwick
 
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Aug 2002
North San Diego County

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Many boards will allow you to run the memory clock and processor FSB at different speeds, so you might be able to run the memory at 200 while retaining 166 for the FSB. Post some more details and I'm sure someone can give you some pointers.
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Old 2005-05-21, 04:20   #3
moo
 
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Jul 2004
Nowhere

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Im wondering if its because ur useing 2 sticks of ram insted of one.... Mabey someone needs to test this get timeings for 2 sticks of high performance ram then use one larger one and see which is better....
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Old 2005-05-21, 11:47   #4
Longshot
 
Mar 2004
Somewhere downrange

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For a long time I have run .154 iterations. The machine was configured like this:

465w Enermax PSU
AMD XP2700+ (2.17 GHz. @333 FSB)
1 stick of Crucial (Samsung sticker on it too) 512 Mb. PC2700 (now gone).
2 sticks of Crucial Ballistix 256 Mb. PC3200 presently installed.
PcChips 848LU Ver. 1.2 Mainboard (supports up to a 3200+ @400 FSB)
Audigy ES sound card (on board sound disabled)
ATI (Crucial) 9200SE 128Mb DDR video card (PCI video support disabled).
Windows ME operating system.
40 Gb. Seagate Barracuda HDD

The 512 Stick failed test #5 of Memtest86 and was replaced with the 2 sticks of Ballistix. Moo, I asked the Crucial tech. support man about two sticks slowing it down and he said it should make no difference. He did mention that if I could crank up the FSB to 200 (400) without O/C ing the CPU that I should do that. I don't think this board will let me do that. I can't understand a 10% or so drop in performance and consider it unacceptable. Crucial will not take the RAM back unless it is defective and I can't prove that it is. Just because my Prime95 iterations are slower is not considered a defect. I ran Memtest86 on these sticks too and they checked out OK.

I have a 2500+ Barton with a 512 stick of generic RAM on a PcChips board doing .179, and a 2800+ Thoroughbred on an ASUS A7N8X-E Deluxe board with 2 sticks of Crucial's standard 512 PC2700 running dual-channel mode doing .137. This CPU is only 80 MHz. faster than the 2700+ and doing the iterations 20% faster. I do only 10 million digit numbers.

I hope some you smart folks can solve this one. Thanks for the help.
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Old 2005-05-21, 16:06   #5
flava
 
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Feb 2003

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What timings do you use with the new memory, and for what timings is it rated?
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Old 2005-05-21, 16:40   #6
Longshot
 
Mar 2004
Somewhere downrange

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Default Memory Timings

The old RAM was 2.5T the Ballistix is 2-2-2-6, I set the BIOS CAS from 2.5 to 2.
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