IC7 and 2×256Mb Corsair XMS3500C2 not stable above 220MHz

Hi,

I already had a topic about having problems to make my machine stable above 275MHz FSB. What I am running now is Dualprime stable, see my sign.

Today I finally managed to POST it at 1:1 (don't know why it didn't work before) and above 220MHz FSB it fails memtest86 the same way as it does with 275/220 (5:4). Test 5, block move, 64 moves, cached - this is the only test it fails, but it does everytime, with a fixed number of errors... No matter what timings, GA settings, VDimm, N/B Strap...

So it seems my Corsair 2×256Mb XMS3500 (Dual Channel) won't go above 220MHz with 2-5-3-2, and if I relax timings things will go even worse... WTF???

I have tried several combinations of timings including the Ram Guy recommended 2.5-6-3-2; 2-6-3-2, 2-7-3-3, 3-7-3-3, 2-5-4-2, 3-8-4-4, etc. I get more and more errors in memtest as timings get relaxed.

VDimm is 2.8V, it won't POST under that (beep - error code of memory problem)...

My VCore was 1.55V with 1:1 as well, I don't think I need more since my CPU runs stable with 275/220...

Have you tested them one at a time? Sounds like you have a bad stick.

Xymurgy said:

Have you tested them one at a time? Sounds like you have a bad stick.

Click to expand...

Not yet, but I need dual channel of course... Bad stick? 220MHz is DDR440 and the stick is rated at 433MHz so I can't RMA it.

Comments? I'm in trouble.

A funny thing is that a friend of mine bought 2×512 TwinMOS PC3200 w/ Hynix chips and it does 245MHz 1:1 3-4-8-8, 2.8V...

:S

i have the same problem as you in that if i relax the timings it gets MORE unstable !! i have xms3200c2 btw.

also, hurry up and try one stick at a time to see if one does better than the other. usually if you put em in both at the same time theyll only run at the slower of the two.

I know about that but I am not interested in if one module is better than the other... I will sell both and buy 2×512Mb something...

I have tested several 875CW boards with my XMS3500 and finally got to try an IS7. It is the latest version 1.2 with the IC7-MaxIII NB sink too. Yep, same problem, but I got proof it's a problem with the board and not the ram.

My 2.40C does wonders on this IS7: so far I'm running 283 fsb Memtest clean at default voltage, which is actually 1.47! It is stable enough to format drives and install an OS, but I doubt it is 3D stable. I only got so far as install WinXP last night. Same CPU maxed out at 287 on a P4C800-E, at 1.6 VCORE, so looks like this IS7 will exceed that no sweat.

However getting ram to run on the IS7 is another matter. My pair of 512 MB XMS3500 have the same problem as you guys: errors out in the #5 test no matter what combo of VDIMM and CAS settings. The ram can't be bad as I just finished running 215, 2-2-2-4 dual channel, sync mode on at 8RDA+. Same sticks have also gone 250, 1:1 (that's DDR500 folks), at 2-2-2-5 on a 4PCA3+ at 3.2 volts!

I had the same problem with an MSI and AOpen 875CW board: they do not like XMS3500. So it's the stink'in board, guys. They don't like BH-5 chips.

I tried some ADATA PC4000 on the IS7 last night and so far I can do 283, 5:4, DDR452 at 2.5-3-3-5, at 2.8 volts. At 1:1 best I can do is 255 or DDR510, 3-4-4-5. You'd think I got lousy ADATA sticks, if all I can muster is DDR510. Well the same sticks have done 282, 1:1 on an 4PCA3+ at 2.9 volts, same 3-4-4-5 settings. That's DDR564! Again, it's not the ram guys, it's the damn board.

I am not impressed with the Sandra benches at 283, 5:4, 2.5-3-3-5: 6000 buffered and barely 2800 unbuffered. 1:1 and DDR510 is barely better on the unbuffered side (2810). On my 4PCA3+ at 277, 5:4, DDR452, 2-2-2-5 I was getting 3300 unbuffered! And with the exact same XMS3500 sticks!

Great overclocking board, but needs help on the mem side. I swear 2.8 VDIMM must be more like 2.7.

Clevor, this is really nice information for us!
At least, for me
Does p4p800, p4c800 or whatever have the same problem?


Bengan

Does p4p800, p4c800 or whatever have the same problem?

Click to expand...

NO!!! The P4C800-E loves XMS3500. I can run 5:4 DDR440 at 2-2-2-5 with the max VDIMM of 2.85 it offers. Above that I can run 2-3-2-5. PAT stays on as long as Turbo is enabled. With my L310xxx 2.40C, I max out on the board at 287, 5:4, DDR452, 2-3-2-5 at 1.60 VCORE and 2.5 VDIMM, where I get 3100 Sandra unbuffered scores.

Funny thing is I've heard some guys have luck with XMS3500 on IS7/IC7 boards.

Same problem with the IC7 and 2*512MB Geil dual plat. 3500 (2, 6, 3, 3).

1:1 = 220

5:4 = 260


Think it's the MB. Kinda **** since the cpu can do [email protected] default V, but I have to use 3/2.




http://forum.abit-usa.com/showthread.php?threadid=22650

"Date: Wednesday, September 03, 2003 05:23 PM
To: [email protected] ([email protected])
Subject: 512MB PC3500 CL2 Black Hi Perf Level II and Abit IC7-G

I own a IC7-G board and 2*512MB Corsair 3200 Low Latency.

Unfortunately they use CH5 chips and my overclock is limited to 250*4 MHz even if my 2.6 P4 supports up to 270 MHz (tested).

I'd like to know if 2*512MB PC3500 CL2 Black Hi Perf Level II has been tested with 5:4 ratio on Abit IC7-G and if positive, which has been the maximum frequency at 5:4? Which voltage? Which latencies?

Is 512MB PC3500 CL2 Black Hi Perf Level II a good choice for my 2.6 P4 or should I buy PC4000?

Thanks for your attention.

From: Tech Support [mailto:[email protected]]
Sent: Tuesday, September 09, 2003 9:04 PM
Subject: RE:{Mushkin#071-716}512MB PC3500 CL2 Black Hi Perf Level II and Abit IC7-G

We have tested those modules on the IC7-G at 5:4 ratio to some degree, but the limitations on overclocking are limited by the chipset, rather than by the CPU or memory. It is very difficult to get any memory to run when the CPU is run above 250mhz at a 5:4 ratio, regardless of the type of memory or CPU. This appears to be a limitation of the chipset, as this has been the case with all the 875 and 865 chipset boards we've seen. Unfortunately we can't guarantee any kind of performance if you run the CPU in a 5:4 ratio, as our memory is intended to be run in a 1:1 ratio. We use voltages of 2.7V for our testing on that board. If you are looking for very high CPU speeds, you would probably be better off using PC4000 memory, as this will allow you to run the CPU and memory in a 1:1 ratio at 250mhz. Unfortunately this memory has higher latencies (3-4-4-8), but the increased clock speed is quite significant.

I hope that helps, please let me know if you need anything else.

Thanks,
Beau"

Hey Myzhi, that reply from Mushkin was interesting.

They are implying ALL 875CW boards have trouble above 250 at 5:4, NOT SO! The P4C800-E and 4PCA3+ will run above 250, 5:4 no problem, 2-2-2-5 or 2-3-2-5 CAS settings with two 512 MB sticks XMS3500 with BH-5 chip. And it will do it with PAT enabled on both boards. From the forums, it seems the problem is with the Abit boards.

Case in point: I've found some guys running the XMS3500 OK on the IC7 and IS7 at CAS 2.0 but they were running 220 fsb. I did find I can run 283 fsb and the XMS3500 at CAS 2.0 but I had to use 3:2 also. Even then, I think I still saw #5 errors.

I e-mailed OCZ to ask them if they got any ram that can do CAS 2 above 250, 5:4 on the IS7. I guess I might as well pass on Geil. Not sure about HyperX. I will be testing some ADATA PC450 tonight, but it uses Hynix chips like the PC4000 so I'm skeptical. Heck, I'd just be happy doing 2-3-3-6 at DDR450 or something on this IS7, the way it can overclock.

anybody who wants stability with the pc3200 use 3:2 ratio........and relax your timings 2,7,4,4....and don't use the GAT settings ........ im getting 267fsb stable 3.21ghz

Theoretically, there is an issue between IS7/IC7 and 512Mb modules... so maybe your problem is a little different. I gained information that others also had a maximum of 220MHz 2-5-3-2 with XMS3500C2, and relaxing timings won't help since the module is designed to be run with tight timings. I've also heard that 2.9 or maybe 3V of VDimm would help us.

And, my CPU does 3.5 as well, with 1.575V... but I can't run it with 3:2, I can boot into windows but Prime95 will fail immediately. Strange, this has to be a mobo problem.

Clevor said:

Well the same sticks have done 282, 1:1 on an 4PCA3+ at 2.9 volts, same 3-4-4-5 settings. That's DDR564!

Click to expand...

Post some benchies about that immediately

Problem is my overclocked rigs are not hooked to the Net, so I can't upload files, and this forum doesn't allow attachments. I didn't take any screenshot anyway. I was not that interested in flogging 270-280+, 1:1, 3-4-4-5 because I got better performance: Sandra unbuffered memory marks (confirmed by 3DMark scores) by running 282, 5:4 at 2-2-2-5. BTW, the guys who are hitting near 300, 1:1 with the ADATA PC4000 are using 3.2-3.4 volts.

I flashed to the 1.6 BIOS on the IS7 and it seemed to improve things. I could run 275, 5:4, 2-3-3-6 Memtest clean with my XMS3500, but I had to drop way down to 260, 5:4 to pass all the 3DMarks. That's only DDR416 . I had really good Sandra unbuffered scores at 270, 5:4, 2-3-3-6 (hit 3k), when you consider at 283, 5:4, 2.5-3-3-5 on the ADATA all I got was barely 2800 or so.

BTW, I e-mailed OCZ and asked them if they had any ram that can do up to DDR480, 5:4, CAS 2 settings near 2.8 volts on the IS7/IC7 and they essentially said they can recommend nothing at the time. They said some PC3700 Gold might do it (I think at 2-4-3-8 or something) and some might not.

I have given up on the IS7, given the fact that XMS3500 performs so well on the two boards I have: 4PCA3+ and P4C800-E. I'm selling it now while I can get a decent price on it. I have an IC7-MaxIII on the way but I don't have high expectations of it based on the IS7 experience. The additional VDIMM will help some but the P4C800-E still outoverclocked the IS7, 287 fsb to 279.