Update: Do I need to set TRFC and TRRD when manually setting memory timings in bios

[blackrain]

I just got this:
http://www.newegg.com/Product/Product.asp?Item=N82E16820231047

timings should be 2.5-3-3-6

anyway, my bios was initially set to auto for the memory timings and read something that was not 2.5-3-3-6

I thnk it was 2.5-4-4-9, but don't remember exactly...it was late last night

Anyway, I changed the setting to manual and changed it to 2.5-3-3-6, rebooted, and the bios seems to have retained these settings and booted without problem.

Just curious...why doesn't the bios automatically set it to the best setting (ie, 2.5-3-3-6)

or is that an indication there is a problem that my bios didn't pick up the best setting...or does that have something to do with my cpu and fsb?

my specs:
abit VT7 (400, 533, and 800 FSB support)
2.6 ghz (400 FSB)
geforce 3

 

[evilsaint]

That is a bit strange, if you BIOS was already set to Auto... Usually Auto signifies that it'll use SPD (serial presense detect) to set the timings that are the RAM itself wants the BIOS to use, but maybe the 'Auto' on your board signifies something else... I've seen it in a few BIOS', mainly on Asus MoBo's, where Auto doesn't use SPD, but instead it just has the MoBo pick out 'safest' timings stability-wise.

 

[blackrain]

want me to take a screenshot of the bios?

 

[Effect]

I've heard of RAM not being picked up at spec'd timings before, doesn't appear to be a problem, might just be the bios thinking the RAM is a different brand, or something to that extent.

 

[blackrain]

How can I confirm that its running okay at the timings I manually set?

 

[Mogadon]

Use CPU-Z

 

[chocoruacal]

Originally posted by: evilsaint
That is a bit strange

It's not strange at all. The SPD on RAM is often set looser than spec to allow it to boot in the widest possible range of mobos.

Use CPU-Z

How does CPU-Z check that the RAM is running okay? It doesn't.

Run Memtest86+ from a booteable floppy or cd to ensure that the new RAM is error free. It's a good idea to let it run at least a few hours (6-7 complete tests).

 

[blackrain]

I'm assuming that cpu-z doesn't rport actual timings because it still shows 2.5-3-3-6 even though the bios was showing 2.5-4-4-9 on auto spd.

I have a followup question. So I changed auto spd to manual and changed the timings to 2.5-3-3-6. There are some other settings that I left alone but i'm curious as to whether I need to adjust these manually as well.

REF to ACT/REF to REF (TRFC): 15
ACT (0) to ACT (1) (TRRD): 3

These were the settings when autospd reported 2.5-4-4-9. On manual, do I need to change these TRFC and TRRD settings?

 

[blackrain]

bump

 

[evilsaint]

Use CPU-Z

How does CPU-Z check that the RAM is running okay? It doesn't.

Run Memtest86+ from a booteable floppy or cd to ensure that the new RAM is error free. It's a good idea to let it run at least a few hours (6-7 complete tests).[/quote]

QFT. 12 Hours+ of MemTest86+ without any errors at any timings that you like, and you can consider at least your memory OC to be stable.

BTW, on the Memory tab in CPU-Z, it shows what timings the memory is currently running at. On the SPD tab (obviously ) it shows what the SPD table on the memory suggests for whatever speed (in MHz) that you have it running.