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View Full Version : Can anyone explain this...?


DocGiggs
01-10-04, 01:40 PM
Okay, most of my current system specs are now uptodate in my sig, however I just bought some new Geil Golden Dragon pc4000 memory and it's acting very, very, VERY wierd....

I can't tell that it's bad though, none of the memory testers I've used show it to be bad at all, but let me explain.

It's suppose to be from 2.6 to 2.95 operation voltage and 250 mhz fsb with 2.5-4-4-7 timing.... good stuff right?

Unfortunately, my asus board won't let me go over 2.8v so I can't experiment as much as I would like until I do the volt mod... yah just been too lazy to buy the parts heh. So I decided to mess around with the timings and see what it can do in the 200-210 fsb range. Here's what I found is intereting and I can't explain.

My CAS latency can only be either a 2 or 2.5. If I try to set it to 3 the system won't post at all. No matter what my fsb is set to. I could set it to 100 and it wouldn't work... odd huh?

Also, my other timings are similar. I can only set the first 2 numbers in a range of 3 to 5. Anything higher or lower will cause the system not to post no matter then fsb. The last number doesn't seem to matter at all, I can set it to anything just about and the system doesn't care (that's the cas to ras precharge).

Any ideas why my memory is behaving like this? I was hoping that if I couldn't do 250 fsb or close right now cause of lack of voltage that I could at least do 200 fsb wtih 2.8v and 2-2-2-5 timings..... sadly I can't better then 2-3-3-5...grrrrr..

memphist0
01-10-04, 01:44 PM
It has to do with how they program the SPD. It's really not that strange. Most PC4000+ doesn't like to be run at CAS 2 or CAS 2.5 even at 200MHz FSB

flapperhead
01-10-04, 02:37 PM
yep, thats right i have some very versitale pc4000 that runs remarkable tight timings. it wont even post at 2-2-2-5 no matter what speed...what is strange tho is not being able to use cas 3, that is what pc4000 is primarily made for. id update the mb bios

ar47bl13
01-10-04, 02:52 PM
I don't think many amd rigs will even boot with cas of three, and if you do get one to boot at cas 3 I heard the performance is TERRIBLE. Cas 3 only works on Intels AFAIK. :-)

johan851
01-10-04, 03:19 PM
I think it depends on the memory chip too, but yeah, AMD systems don't really like CAS 3.

PC4000 uses chips designed for high FSBs and loose timings. These chips just don't run tight timings, no matter what you do to them. Kinda like CH-5 - it does ok overclocking MHz wise, but you can't set it to 2-2-2-5 because it just...won't work. Some chips do tight timings, and some don't.

Grandpa Dan
01-10-04, 03:30 PM
I think it's the Geil. I have yet to see anybody with a P4 rig pimpin their Geil memory. Honestly I've read numerous threads with geil issues on P4 mobo's.

DocGiggs
01-10-04, 05:36 PM
oh well, I love the way my geil looks and I guess I'll have to settle for 2-3-3-5 timings for now. Not to bad I guess...