Hail you gods of timing, latency, and CAS

Hey guys,

I have done some searching and reading around here.. and can't quite seem to solve my problem. Thought I'd appeal to the experts here.

I have an Abit IT7-Max2 board (version 1) all updated, etc. with a P4/2.4B CPU on it. I'd had ONE stick of 512 MB Kingston ValueRam (the DDR-333 PC2700 stuff) and was running the system as follows:

FSB at 150
Multiplier 18x (locked anyway i think)
H/W Strap: Low
DRAM Ratio: 3:4

and had left things like the timings and voltage at their default. I was getting some real great scores on SiSandra and thought I had the system pretty well-tuned and it was running great (except for a RAID problem we'll talk about another day..)

Well, today my new stick of 512 MB Kingston ValueRam (the same exact stick as my first one) showed up and I installed it. Yayy, a gig of ram. Well... XP will not even start with it at the previous settings. I basically have to come all the way back down to default (133 fsb, setting H/W strap and ratio back to default as well) and basically boot it at DDR266. I've tried tweaking the fsb back up a bit but XP just will not boot if I have the ratio at 3:4 and the FSB is raised much above 135-140. Just XP kicks in then the system reboots.

Any ideas ?? Thanks in advance for your input. I'd love to get it back up to performing where it was, especially now that I have twice as much memory. Seems a shame to gain the RAM and lose the speed.

two sticks or ram don't OC as good as one.

yeah it's much harder to oc with two mem sticks

heezer7 said:

two sticks or ram don't OC as good as one.

Click to expand...

Yeh .. well I knew I'd take a minor hit but I never thought it would be so significant...

Anyone who knows of any good tricks, let me know...

heezer7 said:

two sticks or ram don't OC as good as one.

Click to expand...

yeah but not anywhere near as bad as this.

have you tried the new ram on its own?

The biggest limitation of DDR memory subsytems as currently implemented on PC's is the heavy loading of the address bus. This is the factor responsible for the fact that DDR 333 operation is validated for only two dimms, and DDR 400 (at least in the proposed support later withdrawn by SiS and Via) for 1 stick. As always few sticks, and generally less ram total will overclock better. But in the case of the DDR situation as it exists presently the tendancy is more pronounced.

I find the Kingston Value Ram 2700 to be great for 845 based systems. The 512MB stick I tried was stable (as in Quake3 online for a week w/o a crash) at 162 fsb at 3:4 on my BD7-II. This is at the BD7-II limit of 2.7V Vdimm (2.64 actual). You should be able to get more out of an IT7. Do you have one of the newer bioses that supports 3.2V on the Vdimm? (3.0V actual). As well, the timing that works for me is 2-7-3-3. You may have to go up to 2.5 on the cas-ras delay with two sticks.

I agree with james that testing the second stick alone will be educational. But as every stick of the VR 2700 I have tried does 160 fsb or more at 3:4, I'm fairly certain it's ok. The consistancy of this ram is marvelous, especially considering it occurs at such a high level of performance. But better ram will load the bus less. Chances are better of getting 1GB functioning at high speed with something hidously expensive like the Kingston HyperX PC3500 or the Corsair XMS PC3500.

In the end you may find no solution to your dilema. In which case I suggest you send me the second stick As an economy measure I had to part with my favorite 512MB module and the 256MB stick I currently have in the machine only does 160 fsb at 3:4 Not a big deal, as the CPU will only tolerate 162 fsb at the Vcore I am currently limiting myself to. This is one place where the "bigger is better" philosophy needs careful application. 512MB is enough ram for virtually any normal task, I get by on 256. Bigger is always better in regards to clock rate though, so if it comes down to it drop back to a single stick, fsb:memory ratio at 3:4. Vdimm to 2.9V, timing at 2-7-3-3, Vcore at +15%, and inch that fsb up to 160+. The last 2.4b I tried (B0 even) did 167 fsb at +15%, and a single 512MB VR 2700 ought to get there at 3:4 with the benefit of the IT7's extra Vdimm.

larva said:

The biggest limitation of DDR memory subsytems as currently implemented on PC's is the heavy loading of the address bus. This is the factor responsible for the fact that DDR 333 operation is validated for only two dimms, and DDR 400 (at least in the proposed support later withdrawn by SiS and Via) for 1 stick. As always few sticks, and generally less ram total will overclock better. But in the case of the DDR situation as it exists presently the tendancy is more pronounced.

Click to expand...

THank you for your full and thoughtful reply. I knew I'd get some great advice.

larva said:

I find the Kingston Value Ram 2700 to be great for 845 based systems. The 512MB stick I tried was stable (as in Quake3 online for a week w/o a crash) at 162 fsb at 3:4 on my BD7-II. This is at the BD7-II limit of 2.7V Vdimm (2.64 actual). You should be able to get more out of an IT7. Do you have one of the newer bioses that supports 3.2V on the Vdimm? (3.0V actual). As well, the timing that works for me is 2-7-3-3. You may have to go up to 2.5 on the cas-ras delay with two sticks.

Click to expand...

I'll start tweaking a bit more. There is no 2.5 option in my BIOS. Just 2 or 3 for CAS/RAS delay. And yes, my bios allows me to go up to 3.2v.

larva said:

I agree with james that testing the second stick alone will be educational. But as every stick of the VR 2700 I have tried does 160 fsb or more at 3:4, I'm fairly certain it's ok. The consistancy of this ram is marvelous, especially considering it occurs at such a high level of performance. But better ram will load the bus less. Chances are better of getting 1GB functioning at high speed with something hidously expensive like the Kingston HyperX PC3500 or the Corsair XMS PC3500.

Click to expand...

Well, I'll keep playing and getting your feedback. I wasn't expecting to get them both up to 400mhz, but I was hoping for at least better than I have now, which is basically 266 and that sux.

larva said:

In the end you may find no solution to your dilema. In which case I suggest you send me the second stick As an economy measure I had to part with my favorite 512MB module and the 256MB stick I currently have in the machine only does 160 fsb at 3:4 Not a big deal, as the CPU will only tolerate 162 fsb at the Vcore I am currently limiting myself to. This is one place where the "bigger is better" philosophy needs careful application. 512MB is enough ram for virtually any normal task, I get by on 256. Bigger is always better in regards to clock rate though, so if it comes down to it drop back to a single stick, fsb:memory ratio at 3:4. Vdimm to 2.9V, timing at 2-7-3-3, Vcore at +15%, and inch that fsb up to 160+. The last 2.4b I tried (B0 even) did 167 fsb at +15%, and a single 512MB VR 2700 ought to get there at 3:4 with the benefit of the IT7's extra Vdimm.

Click to expand...

But I shouldn't try that with both sticks?

Thanks!

MaineI30 said:

THank you for your full and thoughtful reply. I knew I'd get some great advice.

I'll start tweaking a bit more. There is no 2.5 option in my BIOS. Just 2 or 3 for CAS/RAS delay. And yes, my bios allows me to go up to 3.2v.

Click to expand...

No problem at all, glad to help. The setting I was meaning to refer to *mumbles something that sounds like "brain fart"* is the CAS Latency Time, as it is termed in my BIOS. This is the first value. The fact that you can run 2 with one stick was an unexpected bonus at the clock rates well in excess of 400MHz that I am running. As far as I know the IT7 only delivers 3.0V when set to the 3.2V setting, so don't worry about damaging the ram. 3V should be safe enough, with 2.9 being eminantly safe.

MaineI30 said:

Well, I'll keep playing and getting your feedback. I wasn't expecting to get them both up to 400mhz, but I was hoping for at least better than I have now, which is basically 266 and that sux.

Click to expand...

It's hard to say, as I've not tried multiple dimms. As the single dimm experience I have shows 400MHz is just the tip of the iceberg, there may be a lot more potential in yours, with either 1 dimm or 2. It also may be that your cpu won't stand more than 150fsb, but I really doubt this. But each is unique.

MaineI30 said:

But I shouldn't try that with both sticks?

Click to expand...

Sure, try any combo you can think of. Just make sure you are backed up first I don't think 160+ fsb at 3:4 is feasible with multiple dimms. But you never know until you try. My point was that with 1 dimm you should be able to run 160 fsb with my settings if the cpu has it in it. Good luck.

Update

Changing that latency to 2.5 and raising the vdimm voltage seems to have really helped. I'm running 2.5-7-3-3, with vdimm of 2.9v. Strap is Low, ratio 3:4.

I have been slowly cranking FSB and now am at 153. That means the RAM is again over 400 (407?) which is a very nice development.

I am going to leave things running overnight and will update you on its stability. SiSandra memory tests look good and run well.

Thanks again for the help. More soon.

Running great

Running great. Boy, changing the latency and voltage has made a huge stability difference.

I also noticed SiSandra ID's the RAM chips differently. So I took a closer look. Even though they have the same Kingston model number and sticker on them, the original one has Winbond chips on them and the new one has Samsung chips on them. Hmm.

I've been running and benchmarking with no crashes or problems at FSB 153, which has the RAM at 410mhz. Strap is low and dram ratio is at 3:4.

My SiSandra Memory Bandwidth Benchmark ISSE2 is 2916mb/s and float buffered is 2397 mb/s. Cache & Mem benchmark is 29919 MB/s in 4kB blocks. This setup also has the CPU at 1.6v and it's running at 2.76ghz for those of you who didn't already do the math...

I will keep you updated and I hope this is helpful to others who run into these issues when adding a stick. Thanks to all, especially larva for the tips.

Stay

Re: Running great

MaineI30 said:

Running great. Boy, changing the latency and voltage has made a huge stability difference.

I also noticed SiSandra ID's the RAM chips differently. So I took a closer look. Even though they have the same Kingston model number and sticker on them, the original one has Winbond chips on them and the new one has Samsung chips on them. Hmm.

I've been running and benchmarking with no crashes or problems at FSB 153, which has the RAM at 410mhz. Strap is low and dram ratio is at 3:4.

My SiSandra Memory Bandwidth Benchmark ISSE2 is 2916mb/s and float buffered is 2397 mb/s. Cache & Mem benchmark is 29919 MB/s in 4kB blocks. This setup also has the CPU at 1.6v and it's running at 2.76ghz for those of you who didn't already do the math...

I will keep you updated and I hope this is helpful to others who run into these issues when adding a stick. Thanks to all, especially larva for the tips.

Stay

Click to expand...

That's dissapointing about the Samsung chips, they are crap compared to the Winbond. My Value Ram actually has Kingston branded chips, but as they perform identically to the Winbond branded ones I suspect they are one and the same. Samsung is clearly inferior to both.

If you run on the original stick alone, you could run the machine much harder. Your difficulty with the additional ram is more a product of the inferiority of the Samsung chips as it is the increased load on the bus. With your newfound settings (and even at 2 on the cas latency time) you could run the memory some 20MHz faster. While this will only bring the memory bandwidth up by 10 percent, this fact along with the additonal 10% cpu clock you would gain would result in a faster system. If you really need 1GB or ram (and trust me, few do) run it, but the second chip is no doubt producing a slower machine for any task not ram bound at the 512MB level.

I am going to have to qualify my previously unqualified recommendation of the value ram based on this experience. If I wanted Samsung, I'd use the junk stick laying in the spare room. It is not interchangeable with the winbond or kingston chipped value ram sticks performance wise.

ok i have already posted my problem but i will do it here again with more details
my specs :
athlon xp2000+ locked
abit kx7-333
Enermax 350W PSU
kingston value ram pc2700 512MB with infineon chips (1 stick)
winXP
Asus GeForce4 Ti4600
i have 1cd-rom and a plextor 24x burner both slave to my 2 master hdds
i have 2 pci cards, a sb live5.1 and my NIC (no special brand, it's SURECOM)
I just did an upgrade from 2 256 kingsotn pc2100 to the one above.Before i could go as high as 135 fsb to run have my system running stable at most agressive settings, that is Ultra, Cas 2, 1T
i can raise the Vdim up to 2.85 but i don't see any change.
After getting my new stick i tried to push it but even at 135 it won't load xp, it is restarting after trying to boot the logo.sys(the loading windows image)...
i really have no clue so plz tell me! what is holding me back?
i will appreceate any suggestions!!
thx

here are my full detailed settings in BIOS. The values in () are the alternatives.
Ratio(FSB:AGPCI) : 4:2:1 (3:2:1, 5:2:1)
CPU fast CMD decode : Normal (Fast,Ultra)
CAS : 2 (2.5)
Bank Interleave : 4 Bank (Disabled, 2 B)
Precharge to Active(Trp) : 2T (3T)
Active To Precharge(Tras) : 5T (6T)
Active to CMD(Trcd) : 3T (2T)
DRam Access : 2t (3t)
DReam Queue Depth : 4 level (2L,3L)
DRam CMD rate : 1T Command (2T)

Actually it also still runs in most aggressive settings but only@133 FSB

MaineI30 what chips did you get on your both your ram modules?

hmm i guess i have to make a new thread!!

why don't you stick to the thread you originally posted your problems in, instead of reposting them in other threads?
also read the sticky about memory timings

i did read the sticky, and i have tried from fastest to slowest settings, but it's the same thing, the fsb won't go up.
You are right about posting in one place but i think in this thread my problem is described with most details, that's why i thought that i should stick here!!

Conan said:

ok i have already posted my problem but i will do it here again with more details
my specs :
athlon xp2000+ locked
abit kx7-333
Enermax 350W PSU
kingston value ram pc2700 512MB with infineon chips (1 stick)
winXP
Asus GeForce4 Ti4600
i have 1cd-rom and a plextor 24x burner both slave to my 2 master hdds
i have 2 pci cards, a sb live5.1 and my NIC (no special brand, it's SURECOM)
I just did an upgrade from 2 256 kingsotn pc2100 to the one above.Before i could go as high as 135 fsb to run have my system running stable at most agressive settings, that is Ultra, Cas 2, 1T
i can raise the Vdim up to 2.85 but i don't see any change.
After getting my new stick i tried to push it but even at 135 it won't load xp, it is restarting after trying to boot the logo.sys(the loading windows image)...
i really have no clue so plz tell me! what is holding me back?
i will appreceate any suggestions!!
thx

Click to expand...

you do know this is considered crapping at thread right

indeed.

then why do i not get any replies?? it's the first time that happens that's why i thought making a new thread