Supermicro X7DA8 - Stability probs

[Parabolic]

Hi First post here but I´m an avid reader of these forums.

I´ve got an Supermicro X7DA8 board with 2x Xeon 5160´s - that´s been running unstable ever since I replaced the PSU (the old one blew) and I´ve been using Everest and Prime95 stability tests to stress the board. I´ve tested two separate PSU´s with the same results.

The symptoms are:

1. Board unstable after some running time - about 10 mins (no overheating issues/abnormal temps) - no errors when stressing directly after cold boot.
2. Errors only appear in Everest when stressing the cache.
3. Vcore voltage on CPU2 is lower then CPU1 (cpu1@1.3v - cpu2@1.1)
4. PSU voltages measure lower on this board then on a brand new ASUS board.
5. Most of the caps on this board are Sanyo SEPC 16v/330uf - 2.5v/820uf - and show no signs of stress/leakage.
6. I´ve tested all caps in-circut with an Peak ESR-70 and have found no apparent problems there.
7. Switching/Removing CPU´s has no effect.
8. Memory modules test fine in another board.

Does anyone have any pointers regarding this board/problem ?

[seanc]

Re: Supermicro X7DA8 - Stability probs

What was your old PSU and what is the new one?

[Parabolic]

Re: Supermicro X7DA8 - Stability probs

Old PSU was a FSP GROUP FX700-GLN (700W)
New one is a Gigabyte Superb 720W

[mockingbird]

Re: Supermicro X7DA8 - Stability probs

It's unlikely that the PSU is the culprit because even if it is a lousy PSU, that system's draw is so much less than 720w, the slack would make up for its inadequacy. Especially if it's new.

But then again - your old PSU did blow, but those FSP GLNs are using OST caps. Hmmm. I suggest taking any PSU you can get (I think you need one with a Xeon connector) and running the test with it to eliminate it as a suspect.

[Parabolic]

Re: Supermicro X7DA8 - Stability probs

I've mostly ruled out the PSU - since i´ve tried another known working PSU from another Xeon system.

[mockingbird]

Re: Supermicro X7DA8 - Stability probs

What kind of PSU does that second system use?

[Parabolic]

Re: Supermicro X7DA8 - Stability probs

The other Xeon system has an Antec 500w - switched it over to the problem board and got the same results.

On another note - i´ve found two caps next to the ram modules that the ESR meter tested bad - in circuit - at least their reading was different from all the other caps in the board. Next step is to test them out of the board.

[hardwareguy]

Re: Supermicro X7DA8 - Stability probs

I think you may have found the problem!

A cache test may fail if the data loaded into L1 or L2 from RAM was from RAM with corruption issues due to bad caps.

Use polymers on servers for max reliability.

[Topcat]

Re: Supermicro X7DA8 - Stability probs

On another note - i´ve found two caps next to the ram modules that the ESR meter tested bad - in circuit - at least their reading was different from all the other caps in the board. Next step is to test them out of the board.

Were they lytics or polymers? I'm finding that most all newer SM boards are all polymer. My X8DAI is. I think there's 3 smaller lytics (220uF and lower) on the whole board, and they're associated with the onboard audio. Replace the two in question and see if the symptoms change. my guess would have been a flaky CPU. Had a socket604 xeon act similar on an X5DAL-G.

[bgavin]

Re: Supermicro X7DA8 - Stability probs

I'm purchasing my first Supermicro board for a client's server. It's the X7SBL-LN1, LGA 775 for an E8400. At $170 it is higher priced than my favorite, but now defunct Gigabyte GA-EP45-UD3R.

I'm hoping for rock solid stability, as this is a server build with 2003/R2.
PSU is a Corsair 400W. Four SATA, as two RAID1 pairs.
I will post back on status of all polymer caps.