Completely OT: Memory timings

[aron]

I was asking around for info on this, but I realized that someone here might know.

My basic question is, should PC2700 memory run at 333Mhz.

I have a Shuttle XPC SS51 (Intel P4 with 2.53Mhz/533 FSB). M-Audio 2496 and Radeon 7000 card.

I set the following:

CPU Clock: 133 MHz
CPU RAM Ratio: 4:5
133 MHz FSB * ( 5 / 4 ) * 2 = 333 MHz

The machine never boots into BIOS. It just locks.

If I set it to:

CPU Clock: 133 MHz
CPU RAM Ratio: 1:1
133 MHz FSB * 2 = 266 MHz

It runs but sometimes restarts for no reason.

I'm assuming mediocre memory, but I'm just checking. I returned the RAM for another pair so we will see. It's PNY DDR 2700 memory from CompUSA.

The crappy part is that I need to put in the old kingston 2100 memory to get back to the bias screen so I can change it.

Thanks,

Aron

[Sic]

Not sure if this helps you at all, but read this from tech-report.com

And yes, pc2700 is 333mhz


BIOS

Shuttle's FS51 motherboard is brand new, but its initial BIOS still has plenty of functionality.





Overclock that cube if you dare

Given the SS51's limited airflow, overclocking might not be high on your list. However, if you're into to pushing the little aluminum cube as far as it can go, you can run the front side bus all the way up to 165MHz. The BIOS and chipset also support DDR333, if your memory is up to it.


Shuttle's nebulous memory timings

Shuttle gives you all the standard AGP and memory latency settings if you want to tweak the SS51's performance. There's also a set of 'System Performance' settings that manipulate the DRAM timings.

The only things missing from the SS51's BIOS are CPU and DRAM voltage controls. Upping voltages does produce more heat, which is of special concern in a small form factor like the SS51, but at least a couple of core voltage options would have been nice.[/img]

[black mariah]

It's probably going to be faulty memory. I don't know of ANYTHING that has a higher return rate than memory. I have literally NEVER bought RAM that worked right the first time. Sometimes it didn't even work right the third or fourth time. :?

[aron]

Wow, so what you do? Just keep on returning until it works, or just order away for Crucial memory? The only problem is that ordering away is painful if the memory doesn't work (due to shippping).

I'm thinking it's bad memory, but until now, I've only had one DIMM go bad in all my years of computing.

Thanks!

Aron

[aron]

Sic,

I'm pretty sure after reading that the memory should work with the following:

CPU Clock: 133 MHz
CPU RAM Ratio: 4:5
133 MHz FSB * ( 5 / 4 ) * 2 = 333 MHz

I believe this should be the optimal settings.

Ironically the memory is called PNY Optimal memory!

Aron

[Boofhead]

I think your settings are correct.

Is there an auto detect mode?  Maybe try that.

If that doesn't work there maybe a memory problem - outright or perhaps an  incompatibility.

[Gus]

Aron

   The only time I have had faster memory not work was with some dell systems.  FWIW if you have an older gx1 don't install faster than pc100 the system checks the ram at boot and if it is not pc66 or pc100 it will not boot.

   It could be a timing issue what is the cas timing on the chip?

   check http://www.anandtech.com/ articles on memory.  I like to stay with names I know like Crucial,kingston,corsair etc.    newegg.com seems to have a good selection.  Try to get a cas2 timing.  With memory I think you get what you pay for.

[Gilles C]

I never had any memory problem... until I switched to HP.

I returned 2-3 memory sticks to get one working on my computer and none accepted by my wife's computer.

That later one (my wife's HP) freezes if the memory don't have the same configuration (all the mem ICs on the same side or on both sides) or if I install a faster memory than the one it already has.

I saw it freeze before booting with BIOS in one case, and while loading Windows in another case.

So it seems like you have a memory problem.

Added: http://www.circuitcity.com/display_review.jsp?b=b&c=2&catoid=-10263&OID=71765&com.broadvision.session.new=Yes&com.broadvision.session.new=Yes&ct=0&BV_SessionID=@@@@0661148091.1090940364@@@@&BV_EngineID=ccdhadcmdmfdfelcfngcfkmdffhdffk.0

Results vary, it seems, from that page of evaluations.

I just read that in some cases you need the same brand memories when you have more than one memory stick.

[aron]

OK, just for sake of completeness here is the results that I experienced.

With a second set of RAM, it now boots at 333Mhz.

The following does work:

CPU Clock: 133 MHz
CPU:DRAM Ratio: 4:5

133 MHz FSB * ( 5 / 4 ) * 2 = 333 MHz

Once that's set the following makes a big difference:

CAS Latency
and
DRAM Addr/Cmd Rate

In addition there is safe, normal, fast, turbo, ultra - have no idea what this does in terms of parameters.

The CAS Latency can be set to 2T and above. I can run at 2T and changing this does not seem to make a huge difference.

What does make an _extremely huge_ difference is the DRAM Addr/Cmd Rate! Man, if I got RAM that could run at 1T, this computer would smoke! I can see the difference and it is dramatic. Too bad the memory I bought runs at 2T which is slower.

Prefetch didn't seem to make a big difference.

So you get what you pay for in terms of RAM.