Problem running 1T, Possible bios problem?

[Jay T]

Hi, My board is otherwise perfect & this is the last hurdle I need to overcome. Here are my observations:

4 x 512MB BH5 runs 200MHZ 2t (as it should)
2 x 512MB BH5 runs 200MHZ 1t (according to the bios, but A64 tweaker shows 2T)

2 x 1024 runs 200 MHZ 2t fine, (if you force 1T in the bios the memory runs at 166 MHZ or it simply freezes at post)

Stock settings are used for the test & default memory timings. Bear in mind I'm using a venice A64 & I'm aware the memory controller is on the CPU. But, I've tested both the BH5 & the 1GB Mushkin kit on another Nforce 4 board with the same Venice CPU & both work at 200MHZ 1T. Therefore, this must be an issue with the motherboard. Any ideas? could this be a bios issue?

Cheers
Jamie

[Oldjim]

Have a look at this thread ET: 9nda3j & TCCD 1T problem

[Jay T]

Thank you for the link my friend. I didn't realise that this was a common problem. Well it looks like its just tough luck. Never mind, the Fatality Abit NF4 board I had for a week was garbage. I think I'll stick with the Epox and wait in hope for a bios fix.

[m1mgd00]

Question: Is it better to run at 200 mhz and 2T or 166 mhz and 1T?

I just set up my machine using an Epox 9NPA+ Ultra board with OCZ Dual 2GB (2x 1024) 3200 platinum DDR, and after forcing the BIOS to 1T and the stock speeds (2-3-2-5 at 2.6 volts), I noticed that it was booting up at 166 mhz (no errors in Memtest, though). I haven't yet tried forcing to 200 mhz, and after reading some of the problems other folks are having, I may not even bother. But I'm still not clear whether, from a performance standpoint, I'm better off leaving the BIOS at 1T and downspeeding to 166 mhz or easing back to 2T and letting the RAM fly at 200 mhz.

[Mike abcd]

From the posts I've seen, it only seems to be an issue with the Venice cores and also happens on the Epox NF3 9NDA3 variants. There's been no indication that Epox has looked at it or plans too :-(

Definitely took away any temptation to upgrade my 3000+ winnie...

Mike

[Jay T]

Question: Is it better to run at 200 mhz and 2T or 166 mhz and 1T?

Hi, your OCZ memory uses the same infineon ic's as my Mushkin apparently. The only way to check to see which option is the fastest is to test it. I've haven't tested it but I decided to go with 200 MHz at 2t in the end.

Apparently using 2t instead of 1t loses you around 20% memory bandwidth which results in a frame rate drop of about 4% in games. I really think this board just doesnt like 1t & in my opinion you will have a more stable system running 200MHz at 2t. Maybe epox are trying to fix this in the bios or maybe they know it can't be fixed. Either way they are keeping their lips sealed.

[m1mgd00]

Jay T, thanks for info. It looks like the ~20% benefit of moving from 2T to 1T is negated by the ~20% drop in RAM speeds from 200 mhz to 166 mhz. Since I'm concerned about stability first, I think I'll use 2T / 200 mhz as well.

[Apap]

Here's my solution to the 2T problem.

Overclock the s#%t out of it!

Still working on timings though.

Apap

[jimbobaggies]

Originally Posted by Apap

Here's my solution to the 2T problem.

Overclock the s#%t out of it!

Still working on timings though.

Apap

[Robin B]

To blow a little light on the 1T issue.


Hello,

1T and 2T Command Rate, also known as CPC or Command Per Clock, is a motherboard timing not a memory timing. 1T/2T commands indicate how the system clocks are allocating the timings of a command to the system. 1T = 1 clock cycle and 2T = 2 clock cycles.

On average there may be a performance difference in between 7-10% (depending on who you talk to, platform being run, benchmark used, etc)

1T/2T Command Rates can be setup differently based on manufacture, motherboard, processor type (Intel Vs. AMD) etc. At higher speeds, drivers, board layouts, chipset requirements all can add up to the system performance overall. Changing the 1T to a 2T command rate can stabilize the system if issues arise.

Since 1T-2T command rates are not a memory specification, Crucial does not list this as part of our overall module specification.


THOMAS THOR
Technical Support Analyst
Tel: (800) 336-8896
Tel: (208) 363-5790 (outside US & Canada)
Fax: (208) 363-5501
mailto:crucial.support@micron.com