Sync mem and FSB?

[Chimpie]

Hiya, guys!!

Just a little question. I know it's a newbie's question, but hey!! I AM A NEWBIE!!

I run a Barton @ 13 (locked) * 166 = 2167Mhz. If I was to raise it to 13 * 180 = 2340 Mhz, am I suppose to raise my mem-frequentie to 2 * 180 = 360Mhz?!

If so, is it better to overclock my PC2700 or just to buy PC3200 and UNDERCLOCK it?!

Thx in advance!!

[skattrd]

With AMD you want to keep the memory and cpu frequency in sync, so if you run your cpu @ 180 then your RAM should be @ 180mhz as well, otherwise its a big performance hit.

Try and overclock your RAM, alot of 2700 will run at 3200 speeds, theres only one way to find out .....

If you overclock and get errors try running memtest86 to check wether its the RAM causing the failed overclock

[Shogun]

When you up the fsb on the board it ups the fsb of everything attached to your board, e.g your ram

[kushtibari]

With the A7N8X you can alter the ratio between the ram and the cpu fsb. As Skattrd says its best to keep them in sync but at leat you can play about with the board and see what it'll go to and then alter the ratio to see if the ram can keep up.

[BUFF]

When you up the fsb on the board it ups the fsb of everything attached to your board, e.g your ram

depends on the settings in BIOS, it may but it may not

[Chimpie]

Hmmm... Tried to overclock, with syncing RAM. When I get past 170FSB, I have to loosen my timings on my RAM (From 2.5-3-3-7 to 3-3-3-7). When running Aquamark, it seems that running 2.5-3-3-7 is MUCH better than 3-3-3-7. Raising FSB doesn't make up for the timings... Any ideas?

[BUFF]

When I get past 170FSB, I have to loosen my timings on my RAM (From 2.5-3-3-7 to 3-3-3-7). When running Aquamark, it seems that running 2.5-3-3-7 is MUCH better than 3-3-3-7. Raising FSB doesn't make up for the timings... Any ideas?

What RAM have you got & have you tried increasing Vdimm?
It would be easy to say get some better RAM but thing is that we don't know that your CPU is actually capable of running the 2340Mhz that you want.

[Chimpie]

What RAM have you got & have you tried increasing Vdimm?
It would be easy to say get some better RAM but thing is that we don't know that your CPU is actually capable of running the 2340Mhz that you want.

I think 2340Mhz can definately be reached, I'm using Exos watercooling now!! I could run out and buy some Corsair PC3200, but then I'll have to UNDERCLOCK my RAM... Useful?!

[BUFF]

I think 2340Mhz can definately be reached, I'm using Exos watercooling now!! I could run out and buy some Corsair PC3200, but then I'll have to UNDERCLOCK my RAM... Useful?!

try upping Vdimm first - it would be a shame to buy new RAM if the ols could be coaxed into running what you want.

As for running RAM below specced speeds then you could also tighten up the timings.

[Chimpie]

Tried upping the Vdimm to 2.7. Can run 2.5-3-3-7 till 175Mhz. If I go higher, I can't boot into Windows anymore. I know it's my memory, tried it with loose timings and booted just fine!! Damn, that means new memory...

[hartz]

... If I go higher, I can't boot into Windows anymore. I know it's my memory, tried it with loose timings and booted just fine!! ...

I would not base a decision on ability to boot... I just started with overclocking but from the start I got the Ultimate Boot CD and after every change I run memtest86+ until it fails or at least 2 passes ... When I get a seemingly stable setting, I let it run overnight ... I've had more than one combination of settings which would run fine for 2 passes but give a single error after a few hours of running. This is scary! A single bit error can corrupt a file system, crash the OS or save invalid data.

Just as an example, if the OS decides a data transfer must go to block 101010111100110111101111 on the disk and one bit went awry, you could get your MS word document saved to block 100010111100110111101111, which may not be empty ...

[daniel_owen_uk]

This could be the pci divider, not sure how it works on a7n8x but let me give you a brief run down;

Basically the pci bus needs to run a particular frequency to operate correctly. The frequency is 33mhz, agp needs to be on 66mhz, but if your pci is 33 your agp is likely to be fine.

The PCI bus is either worked out as a division of your fsb or is locked to 33mhz.

If its divided then for example 5:2:1 (fsb:agpci) would be 166:66:33

Now if you up the fsb to 200 and keep that ratio, you get 200:80:40, now neither the agp nor the pci bus would like this. What you would need to do is change the divider to 6:2:1 giving you 200:66:33

Basically try changing your divider to 6 or locking pci if your board supports it.

[BUFF]

T

Basically try changing your divider to 6 or locking pci if your board supports it.

Should be locked by default on an A7N8X (nForce2) & running anything other than a 1:1 ratio is counterproductive on AMD XP.