# Stability with CPU mod (think it has something to do with RAM?)



## michaelb15 (Jun 13, 2008)

So I finally got around to modding my 775 socket to 771, and plopped in a Xeon E5462.. Well, it worked all right, computer booted, and runs fine under low, and medium loads, but then as I was getting ready to overclock it, I ran prime95 just to get a baseline..

Anyway, it runs the first torture test fine, but then the second and third tests will fail after only a minute or 2, even at default clocks. (And general BSOD's when doing anything intensive)

The descriptions of the prime95 tests make me think the issue lies somewhere between the RAM and the CPU. (first test is 'mostly' for cpu, where last one tests the RAM more thoroughly)

I have tried a few things so far, including slacking up the RAM timings a bit, and manually adjusting voltage for the ram and CPU, and nothing has helped much.

Also, before I did the mod, I was using a q8200, and had the FSB clocked to 420 with no issues, so I am kinda curious why, even clocked back to stock clocks, it is still so unstable.

my system:

Asus p5k
e5462
8gb pc2 6400
650w xfx psu

thanks


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## michaelb15 (Jun 13, 2008)

so, I swapped back to the q8200, just to see if the issues carried over..

And, they don't... I am running prime95 with fsb set to 400 (1600mhz) and this is stable as a rock, which eliminates 1 of my worries (was worried that maybe I bent a pin or something while clipping the tabs)

so I am at a loss for what is causing it.

I am planning to try a Xeon with a 1333mhz fsb, specifically a X5460. Was talking on reddit about what I am doing currently, and they pointed out that the e5462 is essentially the same chip as the q8200, except for 3rd level cache being disabled on teh 8200.

So, I am hoping that the issues I have currently are only for the e5462, and won't come up with the x5460. But only time will tell I guess..

Any suggestions on what I should/shouldn't do?

Thanks


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## michaelb15 (Jun 13, 2008)

well, I think I may have a defective CPU. I have tried everything that I can find on the subject, I flashed the xeon micro-codes, played with voltages, and timings, and, nothing helped.

So, I shall try upping to a x5470. I think they have a x10 multi, so it will be much better for overclocking anyway  (I am embarrassed I tried replacing a multi-7 with another multi-7 LOL)


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## Aus_Karlos (Mar 10, 2007)

This mod only seems useful for benchmark purposes. Are you aware that applying the circuit sticker to the CPU you have disabled the CPUs ability to use SSE4.1?

You'll also need to make a custom BIOS file to flash your motherboard with to install the new microcode. ( Windows will usually do this on boot but as you have an "Unknown CPU" the microcode for the Xeon will never bee updated.)
How to Update CPU Microcode in Award or Phoenix BIOS - For LGA 771 & 775

This can brick your motherboard.


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## michaelb15 (Jun 13, 2008)

Aus_Karlos said:


> This mod only seems useful for benchmark purposes. Are you aware that applying the circuit sticker to the CPU you have disabled the CPUs ability to use SSE4.1?
> 
> You'll also need to make a custom BIOS file to flash your motherboard with to install the new microcode. ( Windows will usually do this on boot but as you have an "Unknown CPU" the microcode for the Xeon will never bee updated.)
> How to Update CPU Microcode in Award or Phoenix BIOS - For LGA 771 & 775
> ...


apperently the Xeons can absolutely be stable for regular computing, and, depending on the mobo, certain fetures (such as sse4.1) might not work, but I didn't have any of those issues. As far as I know, everything worked on the CPU, it showed up properly in both the BIOS, and things like cpu-z. (including virtualisation)

The only thing that DIDN'T work for me is cores 1 & 2. If I loaded them beond 80% for more then a min or 2, they would fail. cores 3 & 4 seem to work perfectly. Temps were perfectly reasonable at 50 degrees C under load


but yea, I flashed new microcode, and that did not help the issue. (yea I know the risks of flashing BIOS's I'm not new to the OCing world, and it is nearly impossible to screw up asus easyflash)

But, anyway, if anyone else is looking for info on the subject of 775-771 mods, check here: [MOD] LGA775 Support For LGA771 Xeon CPUs

there is literally 900 pages of forum on the subject, and it is constantly updated/talked about. (apparently an overclocked x5470 is comparable to an i3, so they feel it will be relevant for the next couple years still)


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## michaelb15 (Jun 13, 2008)

well, I got it a bit more stable by adjusting the mobo voltages (increased NB voltage, along with a couple other voltages)

But still isn't perfectly stable..

Anyway, I am giving up with this entire plan for now, and, instead, I am upgrading to a brand new i5-6600k.. I just hope I got the proper adapter mod so it fits in the socket 775. (just kidding)

I may end up getting an x5460 in the future, as I am loaning this current system to a friend.. I may get the itch to mod, and the lga775 systems are so cheap that there isn't much to loose 

If I ever do end up doing that, I'll come back and post the results.


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