Help me get my E6400 past 410 FSB

[ryansebiz]

I've gotten my E6400 up to 410 FSB on my Asus P5W DH Deluxe, but can't get any further. When I try FSB 415 it won't POST. I have to shut down the PC then turn it back on to get back into the BIOS (resetting won't work).

Then I get this BIOS error message: Overclocking failed or Overvoltage failed! (lol)

I tried FSB 415 by upping the vCore to 1.4v and the vDIMM to 2.1v - not only would that not POST, it cleared my BIOS!

I also tried raising vMCH to 1.65v and the vICH to 1.2v but that didn't POST either.

What should I try next? Here's my stable FSB 410 settings:

FSB 410
DDR2 820
vDimm 2.0v (can go up to 2.05v, 2.1v, etc.)
vCore 1.375v (can go up to 1.3875v, 1.4v, etc.)
vFSB 1.2 (can go up to 1.3v, 1.4v, 1.5v)
vMCH 1.55 (can go up to 1.65v, 1.75v, 1.85v)
vICH 1.05 (can go up to 1.20v)
3280mhz

 

[theelectic]

You're probably RAM limited at this point. In all likelihood your 6400C4 is ProMOS or Elpida, which don't overclock well.

 

[wdn]

I've gotten my E6400 up to 410 FSB on my Asus P5W DH Deluxe, but can't get any further. When I try FSB 415 it won't POST. I have to shut down the PC then turn it back on to get back into the BIOS (resetting won't work).

Then I get this BIOS error message: Overclocking failed or Overvoltage failed! (lol)

I tried FSB 415 by upping the vCore to 1.4v and the vDIMM to 2.1v - not only would that not POST, it cleared my BIOS!

I also tried raising vMCH to 1.65v and the vICH to 1.2v but that didn't POST either.

What should I try next? Here's my stable FSB 410 settings:

FSB 410
DDR2 820
vDimm 2.0v (can go up to 2.05v, 2.1v, etc.)
vCore 1.375v (can go up to 1.3875v, 1.4v, etc.)
vFSB 1.2 (can go up to 1.3v, 1.4v, 1.5v)
vMCH 1.55 (can go up to 1.65v, 1.75v, 1.85v)
vICH 1.05 (can go up to 1.20v)
3280mhz

First of all your vDimm is supposed to be 2.1 volts so less than that and you are actually undervolting it. You can also set it to 2.2 volts but at least 2.1.

Set your memory timings to 5-5-5-18. I am not familiar with your motherboard so you need to get somebody else to tell you how to do that. Also those Asus boards have voltage droop. I would set the core voltage higher first, see how high you can get the FSB and then drop it back. Like 1.45 volts.

 

[ryansebiz]

First of all your vDimm is supposed to be 2.1 volts so less than that and you are actually undervolting it. You can also set it to 2.2 volts but at least 2.1.

Set your memory timings to 5-5-5-18. I am not familiar with your motherboard so you need to get somebody else to tell you how to do that. Also those Asus boards have voltage droop. I would set the core voltage higher first, see how high you can get the FSB and then drop it back. Like 1.45 volts.

Thanks wdn.

I tried all three of your suggestions and they helped. In addition I increased the vMCH to 1.65v to vICH 1.20v. That got me up to 420. Anything over that and XP won't load.

Here's what I'm running now:

vDIMM 2.1v
vCore 1.5v
Timings: 5-5-5-18
vFSB 1.2v
vMCH 1.65v
vICH 1.2v

Any ideas to get me over FSB 420?

Update: I can't last seven seconds in Orthos. I can at 410 but not 420 no matter how much voltage I add.

 

[theelectic]

Any ideas to get me over FSB 420?

Have you tested the limit of your RAM? Drop your multiplier and up your RAM voltage to 2.2V or more, if you can't get past 420 then it's your RAM that's a bottleneck. I got my crap ProMOS based OCZ Plat Rev 2 to 460, but only with 2.3V through them. More voltage made no difference. I felt lucky though since most ProMOS will only do around 420-430.

 

[ryansebiz]

Have you tested the limit of your RAM? Drop your multiplier and up your RAM voltage to 2.2V or more

This is my first successful OC and I've never tested RAM before. Do you mean drop the FSB multiplier (to 266), up the vDIMM to 2.2v and test it (in Orthos)?

 

[wdn]

What you need to do is find out what is your CURRENT memory speed including the timings.

Get CPU-Z utility and show us what the numbers are. Cick on the main CPU tab and memory tab like this. The FSB-to-DRAM ratio is important. That is the second number printed out in the Timings box it should be 1:1 Do not let you motherboard set this rato automatically you must set it yourself. On the DS3 if is called System Memory Multiplier and you would set it to 2.0 so that FSB 410 turns into DDR2 820. Let's just confirm it is really 820 on the memory side


For an E6400 you should be running at 1:1 for best results. Look at the photo. I am flying by remote control here because I am not an Asus guy, I know how to set all this on a Gigabyte DS3 but not Asus. But regardless how you set BIOS settings on Asus the screens look the same in CPU-Z so let's see yours.

Do not even attempt Orthos until you have the situation figured out, OK? Let's get your cooling set up properly too first.

 

[wdn]

The other thing and this might not be the thing you want to hear, is this: There is no guarantee you can get past 410 or even get to 410 FSB. Not all Conroes will get there. Even getting to 3280 MHz is a respectable overclock. I encourage you to continue and to be optimistic. Some will not get over 2800 MHz.

 

[ryansebiz]

I had to drop back down to 400 FSB because 410 wouldn't last more than five minutes in Orthos. Here's my settings:

400 FSB
DDR2 800
5-5-5-18 1:1
vDimm 2.1v
vCore 1.425v
vFSB 1.2v
vMCH 1.65v
vICH 1.2v
3200mhz

(vCore 1.4v, vFSB 1.2v, vMCH 1.55v, vICH 1.05v wouldn't pass Orthos)

 

[wdn]

Good, that confirms your memory settings all right. Thanks.

I am starting to thing memory now. Corsair 6400C4 is generally crap with a wide variation of performance. The performance is all over the place. Their quality control is sketchy, to say the least. Did you get it from newegg? They had a batch where they had to recall the entire batch.

I had to RMA one pair that would not run stable over 350 FSB which is far under their published spec. What I would do is get memtest-x86 and run it at 3200 MHz with your FSB 400 and ratio 1:1 exactly 2.1 volts on the memory and run it overnight. If you get 1 single memory error RMA it back to Corsair.

Another way to test memory is to drop your FSB back to the stock 266 and set the memory multiplier to 3. Now you know you are not pushing your CPU at all but the memory is running at DDR2 800. Now gradually go up by 5 FSB at a time. If it craps out around DDR2 840 again you know it is the memory. because the CPU is not even going fast at that speed. If on the other hand your memory is fine at up to 850 or 900, then it is the CPU. You have a bottleneck somewhere so testing both ways will tell you where it is.

 

[theelectic]

You need to see if your RAM will do 400 FSB (DDR2-800) at CAS4 (the rated timings) and stock voltage before you do anything else. Lower your CPU multiplier as much as possible to get it to stock E6400 speeds (set it to 5x CPU multiplier and 400FSB). If memtest86+ 1.7 fails at stock RAM speeds, you need to get that fixed (RMA'd) before doing anything else.

 

[ryansebiz]

Did you get it from newegg? They had a batch where they had to recall the entire batch.

I bought it from Newegg on January 14.

What I would do is get memtest-x86 and run it at 3200 MHz with your FSB 400 and ratio 1:1 exactly 2.1 volts on the memory and run it overnight. If you get 1 single memory error RMA it back to Corsair.

OK I'll do that tonight.

Another way to test memory is to drop your FSB back to the stock 266 and set the memory multiplier to 3. Now you know you are not pushing your CPU at all but the memory is running at DDR2 800. Now gradually go up by 5 FSB at a time. If it craps out around DDR2 840 again you know it is the memory. because the CPU is not even going fast at that speed. If on the other hand your memory is fine at up to 850 or 900, then it is the CPU. You have a bottleneck somewhere so testing both ways will tell you where it is.

Thanks wdn. I'll try that with memtest and post the results.

 

[ryansebiz]

You need to see if your RAM will do 400 FSB (DDR2-800) at CAS4 (the rated timings) and stock voltage before you do anything else. Lower your CPU multiplier as much as possible to get it to stock E6400 speeds (set it to 5x CPU multiplier and 400FSB). If memtest86+ 1.7 fails at stock RAM speeds, you need to get that fixed (RMA'd) before doing anything else.

Thanks theelectic. I'll try that and let you know what happens.

 

[wdn]

I bought it from Newegg on January 14.

In that case you apparently bought from the same bad batch of memory as I did I bought a little earlier than you did. I bought 2 sets and already had to RMA one set back to them, and I am in the process of RMA'ing the other set.

The good news is the 1st replacement set "seems" to work fine and runs much faster too. I get stable 4-4-4-12 at 460 FSB, beyond that I need to loosen it up quite a bit. I say seems because I did not run memtest as of yet

 

[ryansebiz]

Here's my memtest results. All tests w/ vDIMM 2.1v, 5-5-5-18 timings and 3:1 divider:

CPU: 266
DDR2: 800
10 hours (overnight) 0 errors

(the rest were ran for 4 hours each with 0 errors)

CPU: 273
DDR2: 819

CPU: 277
DDR2: 831

CPU: 280
DDR2: 840

CPU: 283
DDR2: 849

CPU: 287
DDR2: 861

So I guess the problem isn't with the RAM. What should I try next?

 

[theelectic]

So I guess the problem isn't with the RAM. What should I try next?

Unfortunately it could still be the RAM - you did not test it at its rated speed, timings, and voltage. That would be DDR2-800, 4-4-4-12-2T, 2.1V. 5-5-5-18 is the JEDEC standard, but if you RAM can't do the CAS4 it's rated for, best to RMA it.