Jump to content
Corsair Community

Problem with TWIN2X4096-8500C5DF and Abit IP35 Pro XE - C1 POST ERRORS


mabian

Recommended Posts

Hello,

 

I have a new system with Abit IP35 Pro XE Bios 11 and the Dominator TWIN2X4096-8500C5DF G Kit.

 

I have severe C1 problems that prevent POSTing when I start cold the system.

 

By default the RAMs are driven at 816 MHz (FSB 340 MHz) with 1.2 FSB/RAM multiplier, and it seems the system works with this settings.

 

But, I have tried bringing them to 1020 MHz using 1.5 multiplier, also rising voltage to 2.2V; the system has rebooted warm correctly and gone over a 6h stress test with prime95 with zero problems; now, after 12 hours off, it did not reboot - had to reset CMOS to get back to get past POST.

 

I have the RAMs in the brown slots because I've been told that the blue slots have compatibility issues with these memory modules.

 

Timings are by SPD, not tweaked manually. It seems they are running at 5-5-5-18-2T.

 

Is there something wrong here or am I really unable to run the RAMs at around 1 GHz on this system?

 

Thanks,

Mario

Link to comment
Share on other sites

  • Corsair Employee

Please make sure that you have the latest bios and load setup defaults and then set the memory Voltage to 2.1 Volts then set the timings manually to the tested settings for the specific module you have, and test the modules one at a time with http://www.memtest.org to be sure one is not failing. If you still get errors, please follow the link in my signature “I think I have a bad part!” and we will be happy to replace them or it! However, if you get errors with both modules that would suggest some other problem and I would test them in another system or MB to be sure. In addition, with some MB's (Mostly ASUS) you have to disable legacy USB in the bios when running any memory test.

.

Link to comment
Share on other sites

Thank you. I have already flashed to latest BIOS and reset CMOS. The problem arises only on cold boot after changing RAM settings in BIOS - If I boot after resetting CMOS, enter BIOS, tweak FSB:RAM multiplier, save and reboot I can work and stress the system for hours without a single glitch.

And CPU-Z reports the RAMs are running at 1020 MHz (FSB 340 MHz, RAM bus 510MHz, multiplier 1.5)

 

I thought that it was enough to change the FSB:RAM multiplier, then I also tried setting voltage to 2.2V (they were advertised for such a setting where I bought them). But as soon as the machine is turned on after a while of power off, C1 errors prevent POSTing.

The RAM only seem working ok with FSB at 340 MHz, RAM bus at 408 MHz, (1.2 multiplier). I already tried changing slots and using one RAM at a time, but once the C1 problem comes up the only way out is resetting the CMOS.

 

Interestingly, CPU-Z reports the RAMs as PC-6400 (400MHz) and not as PC-8500 as expected (but I have the original package and they are the model already mentioned). I have had absolutely zero instability once the system has passed POST, the only (severe) issue is when the system has been powered off for a while.

 

- Mario

Link to comment
Share on other sites

That may be normal since you are over clocking the CPU set the memory frequency at DDR800 and try to over clock the CPU a bit more and lower the CPU Multiplier a bit.

 

Why do you say I'm overclocking the CPU? Running with FSB @340 MHz is 2% overclocking... my problem is when changing the RAM:FSB multiplier (current value is 1.2).

 

It also seems I shouldn't able to tweak the CPU multiplier... or am I wrong?

 

BTW, system is going rock solid with FSB 340, RAM multiplier = 1.2 -> DDR2 running at 816 MHz; so the question is: am I really missing something in the gap 816->1066? Is going through the hassle of finding the way to use memory @1066 MHz worth when I could then find out that my system is only 3-4% faster? (I've seen some interesting tests about it here: http://www.digit-life.com/articles3/cpu/ddr2-800-vs-ddr3-1333.html)

 

Thanks,

Mario

Link to comment
Share on other sites

  • Corsair Employee

You should be able to set the memory frequency manually to DDr1066 but as I said before you may have to over clock the CPU to get the full speed.

And no the difference on DDR800 and DDR1066 is nominal on Intel platform MB's about 3-6%.

Link to comment
Share on other sites

Mmm things are not so good.

 

I haven't yet done memtest, but the problem is absolutely on cold start, so I don't know if memtest can detect such kind of problems.

 

When the system starts, be it with RAM at 816 MHz or 1020 MHz, it's rock solid.

 

But when it has stayed off for a while, then it's C1 motherboard error until I reset CMOS and keep powered off for a while.

 

I haven't other systems available to test the RAM on, this is a brand new system and I haven't been able to have it stable in a week of trials.

 

Full story so far here:

 

http://www.theraptorpit.com/forum/index.php?showtopic=2428

 

Any hint?

 

- Mario

Link to comment
Share on other sites

Current settings I'm trying (FSB @334Mhz, BIOS doesn't allow 333MHz) do not overclock the CPU.

 

Anyway, I never went over 340MHz, which is a very moderate overclock (2%)...

 

Now system is ok after six hours of power off, will need a couple more tests, one of those is next evening after 12 hours power off.

 

Fingers crossed...

 

- Mario

Link to comment
Share on other sites

NP Please do let me know and did you update the BIOS yet? if not I would try that as well.

 

I have already flashed BIOS to latest v11.

 

Anyway, after the latest tweaks I made yesterday (reconfigured BIOS parameters as suggested in the other thread, swapped RAM module slots) the system has always booted correctly, even after 12 hours power off, on warm reboot and another 2 hours power off.

 

Hope it means something...

 

Thanks,

Mario

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...