HP Z420 with Xeon E5-1650 (v1) - BIOS sees only 32GB out of total 64GB of RAM

[smihaila]

Hi SDH,

I think you nailed it and you have truly found what the real root cause for my issue was!!!

I've just pulled ALL the 6 (six) versions of that PDF information material from HP:

- v1, dated 10/18/2010:

http://www8.hp.com/h20195/v2/getpdf.aspx/c04164501.pdf?ver=1

- v2, dated 08/01/2012:

http://www8.hp.com/h20195/v2/getpdf.aspx/c04164501.pdf?ver=2

- v3, dated 08/22/2014:

http://www8.hp.com/h20195/v2/getpdf.aspx/c04164501.pdf?ver=3

- v4, dated 04/01/2015:

http://www8.hp.com/h20195/v2/getpdf.aspx/c04164501.pdf?ver=4

- v5, dated 07/01/2016:

http://www8.hp.com/h20195/v2/getpdf.aspx/c04164501.pdf?ver=5

- v6 (latest), dated 06/01/2017:

http://www8.hp.com/h20195/v2/getpdf.aspx/c04164501.pdf

Searching for "Z420" through each of the 6 docs, will always show UN-buffered as type of accepted ram (with different variations for frequency and ECC vs. non-ECC).

Also, the HP's "Maintenance and Service Guide" doc available here:

http://h20628.www2.hp.com/km-ext/kmcsdirect/emr_na-c03424977-1.pdf

... shows in page 33 and 113, very clearly that ONLY UN-buffered DIMMs are supported. And more than that, this doc is more specific, and stating ONLY ECC for Z420.

The same page 113 shows for Z620 and Z820 (as opposed to my model which was Z420) that both UN-buffered and Registered RAM is supported.

Your answer has clearly addressed the issue. How come I missed this registered vs unregistered aspect, and also, how come the PC was still able to function (pretty stable) with buffered/registered with 32 out of 64GB recognize, I cannot fathom. As far as I'm concerned, maybe I have focused only on ECC vs non-ECC and took those 2 ebay sellers' words for granted. Very probably, those 8 x 8GB registered ECC DIMMs were pulled from a bigger workstation, like Z620 and Z820.

Thanks so much for your solution!

[MtothaJ]

---

@smihaila wrote:

Ok, so here is the exact info on the RAM chips that I was having:

- Label with Samsung logo on it:

8GB 2Rx4 PC3-10600R-09-10-E1-P0
M393B1K70BH1-CH9Q1 0929

- Label with HP logo on it:

7Q0995
P/N 500205-571

That particular HP part number is something similar to this, except that my RAM was fully enclosed in shiny, thick metal enclosure for better thermal transfer:

https://www.amazon.com/HP-PC3-10600-DDR3-1333-Registered-500205-571/dp/B00A8WQL26

https://www.newegg.com/Product/Product.aspx?Item=1X5-007B-000H6

So as you can see, it's definitely ECC and Registered (aka buffered) DDR3 ram, clocked at 1333 Mhz. The newegg link does not mention ECC explicitly, only Amazon.

You have mentioned that in no way a registered/buffered DDR3 would work in a Z420. But I find such assertion debatable, since (1) 2 different stores have both confirmed that such LGA2011 based mobo and Xeon E5 series CPU would work only with ECC + Registered. And (2) 32 GB out of 64GB were properly recognized by BIOS. And buffered vs. unbuffered is a quite radical difference, right?

So, I can only speculate that either:

a. The 1333 MHz memory is considered too slow/legacy for that mobo and bios and perhaps by DOWNgrading the bios one may be (pleasantly) surprised to see it suddenly working.

b. Or, something on the mobo was defective (mem controller can't be 'cause that's integrated into CPU), or

c. LGA2011 socket pin bent (hard to believe with the tower shipped with everything mounted on). CPU was also testing fine with any diag tools.

d. Or the DIMM slots 1-4 having some mechanical defects?

It is odd that HP does not have a situation like this depicted in any of their troubleshooting use-cases or info from past experience with other customers.

Very intriguing as a problem. Unless someone can chime in with some HP docs that clearly reveal that such RAM shouldn't have worked at all in such system.

Thanks again.

---

The RAM type (ECC Registered) you are using is entierly fine for the Z420. I had 8x8GB ECC Registered in mine and it worked fine - showed up in both bios and WIndows.

Make sure you have the latest bios installed, try clearing the cmos, however since you seem to have done quite a lot of testing, IMHO if you cannot get even a single stick of RAM to work in banks 1-4 then it may be a motherboard or CPU defect.

[smihaila]

Hi MtothaJ,

Very interesting confirmation from you - in regards to the 8x8GB ECC Registered having worked fine in your Z420! Was it the same freq i.e. 1333 MHz?

The BIOS was upgraded to latest (the version originally found wasn't that old - only 1 release behind).

The only thing I didn't get to try was to removing the cmos battery completely - used only the tiny push button but made sure to keep it depressed for about 1 minute :-). I did see the bios warn message stating that settings have been restored, even though the date & time were not reset. I guess that was fine 'cause the cmos was still having the battery available.

It is funny that nowI don't know what to trust as documentation reference - 2 HP docs or your setup + the other ebay e-stores who were basically saying the same thing as you i.e. PC3-1600R should work (they were both quoting the same freq/clock rate). Perhaps the 1333 Mhz in ECC+registered mode is kind of the lowest limit that z420 can go? But there are ECC+registered DDR3s that are clocked at an even lower rate, right?

Perhaps it was a defect after all and I am overanalyzing. The other funny thing is that I've sent an e-mail to the seller arguing that the issue was the wrong RAM :-). They will sort it out and I'll eventually get a working, stable replacement within a week. And I've ordered a Gigabyte GTX 1060 ITX mini 6GB video card to go with that, in the meantime 🙂

Thanks again.

[MtothaJ]

---

@smihaila wrote:

Hi MtothaJ,

Very interesting confirmation from you - in regards to the 8x8GB ECC Registered having worked fine in your Z420! Was it the same freq i.e. 1333 MHz?

The BIOS was upgraded to latest (the version originally found wasn't that old - only 1 release behind).

The only thing I didn't get to try was to removing the cmos battery completely - used only the tiny push button but made sure to keep it depressed for about 1 minute :-). I did see the bios warn message stating that settings have been restored, even though the date & time were not reset. I guess that was fine 'cause the cmos was still having the battery available.

It is funny that nowI don't know what to trust as documentation reference - 2 HP docs or your setup + the other ebay e-stores who were basically saying the same thing as you i.e. PC3-1600R should work (they were both quoting the same freq/clock rate). Perhaps the 1333 Mhz in ECC+registered mode is kind of the lowest limit that z420 can go? But there are ECC+registered DDR3s that are clocked at an even lower rate, right?

Perhaps it was a defect after all and I am overanalyzing. The other funny thing is that I've sent an e-mail to the seller arguing that the issue was the wrong RAM :-). They will sort it out and I'll eventually get a working, stable replacement within a week. And I've ordered a Gigabyte GTX 1060 ITX mini 6GB video card to go with that, in the meantime 🙂

Thanks again.

---

My kit was 8x 8GB 1866Mhz ECC Reg - exactly this one:

http://www.ebay.de/itm/8x-8GB-64GB-RDIMM-ECC-REG-DDR3-1866MHz-RAM-HP-Workstation-Z420-Z620-Z820-E2Q9...

If you look in the auction you can see the seller added a Z420 bios screen showing the 64GB and the RAM being ECC Registered (ECC RDDR3) just as proof that it works. The Z420 is a C602 chipset and it supports ECC Registered RAM provided a Xeon processor is used. Since its a 4 channel memory architecture, best performance is using 4 RAM sticks (1 per channel) but frankly speaking whether you use 4 sticks or 8 it doesn't make any noticable difference to performance. Main thing is that all sticks are the same type / speed / brand ect.

With a E5-1650 v1 it run at 1600mhz, with a E5-1650 v2 it run 1866Mhz.

In your case the speed is definietly not the issue - 1333Mhz under normal circumstances would work entierly fine. Basically the machine doesn't care - it will run at the top default speed of your CPU or RAM whichever is lower.

[smihaila]

Got it, super cool! I do see one important difference in your case, though: Your boot block is more recent (2013 instead of my 2011). Hopefully that doesn't matter too much.

Thanks for the new info, looks great.

One more question if you don't mind: I also have the option to upgrade from the existing E5-1650 v1 CPU to either E5-2650 v2 (8 cores and more L3 cache but lower clock) or E5-1650 v2 (6 cores, same cache as 1650 v1 but lower clock that 2650 v2).

Benchmarks on the internet seem to show almost similar performance. Although the E5-2650 v2 has a lower TDP / heat, while E5-1650 v2 has higher clock rate and better single core perform (albeit higher TDP).

Both v2 CPU-s were released almost at the same date (Sept 2013 vs Aug 2013) and same 22 nanometer technology.

Which one would you personally go for? Use case: general use (multimedia / HTPC / watching HEVC-encoded movies, massive web browsing i.e. 100 tabs at once via Pale Moon - a lightweight Firefox fork similar in resource use to ol'good Opera 12.x) but I'd also like to pair it with an NVidia GTX 1060 6GB for games (games are a new thing for me). I would also like to not have thermal issues, if possible.

Thank you!

[bivoy]

Hi, try to remove 4 stick and fill only slots with the same collor - there should be always 4 slots same solor, and another 4 in another color. If some slots do not work, you will see it - then slots KO or pin bent. Then do the same for 4 slot and test all your memory dimms.

Also check if your all 8 dimms reads the same 2Rx4 .....on the sticker, or some 1Rx4, 1Rx8 etc, this may cause problem sometimes.

And for CPU upgrade 1650v1 to something else - do not do it, 1650V2 is not much faster,  not makes sense, invest in graphics or SSD , or find cheap 1660/1680v1 (and mind pins when swaping 🙂 )

[MtothaJ]

---

@smihaila wrote:

Got it, super cool! I do see one important difference in your case, though: Your boot block is more recent (2013 instead of my 2011). Hopefully that doesn't matter too much.

Thanks for the new info, looks great.

One more question if you don't mind: I also have the option to upgrade from the existing E5-1650 v1 CPU to either E5-2650 v2 (8 cores and more L3 cache but lower clock) or E5-1650 v2 (6 cores, same cache as 1650 v1 but lower clock that 2650 v2).

Benchmarks on the internet seem to show almost similar performance. Although the E5-2650 v2 has a lower TDP / heat, while E5-1650 v2 has higher clock rate and better single core perform (albeit higher TDP).

Both v2 CPU-s were released almost at the same date (Sept 2013 vs Aug 2013) and same 22 nanometer technology.

Which one would you personally go for? Use case: general use (multimedia / HTPC / watching HEVC-encoded movies, massive web browsing i.e. 100 tabs at once via Pale Moon - a lightweight Firefox fork similar in resource use to ol'good Opera 12.x) but I'd also like to pair it with an NVidia GTX 1060 6GB for games (games are a new thing for me). I would also like to not have thermal issues, if possible.

Thank you!

---

To run the v2 CPU's you need the 2013 bootblock. There has been plenty written on this subject - feel free to browse the forum for more info.  

The E5-1650v2 has the advantage that it can be overclocked in the Z420 by using Intel XTU. You are still limited to a 130W TDP limit but the performance gains are still substantial especially when fully utilizing just 1-2 cores (as many programs do).

The E5-2650 v2 has locked multiplier so it doesnt benefit from the above, while the E5-1650 v1 - while multiplier unlocked - does not respond to any tweaking in XTU (core multiplier sliders are grayed out).

[smihaila]

---

@bivoy wrote:

Hi, try to remove 4 stick and fill only slots with the same collor - there should be always 4 slots same solor, and another 4 in another color. If some slots do not work, you will see it - then slots KO or pin bent. Then do the same for 4 slot and test all your memory dimms.

Also check if your all 8 dimms reads the same 2Rx4 .....on the sticker, or some 1Rx4, 1Rx8 etc, this may cause problem sometimes.

And for CPU upgrade 1650v1 to something else - do not do it, 1650V2 is not much faster,  not makes sense, invest in graphics or SSD , or find cheap 1660/1680v1 (and mind pins when swaping 🙂 )

---

1. RAM bank testing: I tried it all: like putting 2 x 8GB in 2 black slots in front area and 2 x 8GB again in 2 black slots in rear area. Or 1 x 8GB in DIMM 1/black and 1 x 8GB in DIMM 8 / black. Or putting stuff in pairs (front-back area) into the white slots. The results were always the same: BIOS seing only the stuff inserted into the rear area (banks 5...8) and nothing in banks 1...4.

2. Checking all th 8 DIMM chips individually. Yes, besides the same HP part number and Samsung UPC / serial number, they were all showing the same "2Rx4" coding on their tags.

3. CPU upgrade from 1650v1 to either 1650v2 or 2650v2. I know the performance differential shouldn't be that higher. But I forgot to mention the cost: The 1650v1 that was installed (and worked with HP Z420 bios boot block dated 2011) is evaluated by the ebay store for $110. The difference to get the 1650v2 is +$30 and to get the 2650v2 it is +$40. In the light of this new information (cost), would you still NOT do the upgrade? Any performance gain with gaming / higher single-clock freq?

Thank you!

[smihaila]

---

@MtothaJ wrote:

---

---

To run the v2 CPU's you need the 2013 bootblock. There has been plenty written on this subject - feel free to browse the forum for more info.  

The E5-1650v2 has the advantage that it can be overclocked in the Z420 by using Intel XTU. You are still limited to a 130W TDP limit but the performance gains are still substantial especially when fully utilizing just 1-2 cores (as many programs do).

The E5-2650 v2 has locked multiplier so it doesnt benefit from the above, while the E5-1650 v1 - while multiplier unlocked - does not respond to any tweaking in XTU (core multiplier sliders are grayed out).

---

Thank you for this - considering your new info, yes, it does make sense to upgrade to E5-1650 v2 (even if comparing to E5-1650 v1 the 100 MHz higher base clock rate is not too much). And the ebay store is only asking for $30 more for this upgrade.

And regarding the 2013 bootblock, your intervention was pure telepathy - in sync with my similar finding on a web forum on tomshardware, I guote:

"-To determine if the Z420 can support the v2 CPUs, look in the F10 BIOS setup for the boot block date
=> If the Z420 has a boot block date of 12/28/2011, it supports only the v1 CPUs
=> If the Z420 has a boot block block of 03/06/2013, it supports both the v1 and v2 CPUs.
HP does not support updating the boot block. "

Such requirement couldn't be more than welcome. Because by doing the upgrade to the 1650 v2, I would have a double confirmation that the seller will definitely give me another used Z420, completely different than the one which they have sent originally (I'm not sure if they "mix and match" mobos and cpus, and prefer instead to pick up a completely different Z420 from the recycled stock. And move only the RAM around). I shall explicitly ask them to triple-check that the bios shows (a) the 2013 bootblock, (b) v2 suffix for the CPU, (c) Right memory assignemnts in the banks and the memory type.

Thanks a lot for all this great info! I'll ask them to go with 1650v2 upgd. And either replace the 1TB spinning HD with, or add on base of that, also a 256GB SSD drive. Because I have noticed that the 1TB 7200 rpm hdd (a Western Digital) was super-noisy - either because the original owner has put it thru lot of intensive use, or it came from somewhere else, or maybe this Z420 does not have too much sound proofing / rubber washers around bays and hdd screws etc.

Along with those 2 upgrades, I also have this in my list of notes to ask them about for the upcoming Monday Feb 26 2018 (this is when the returned pc arrives back to them):

- Ask to take care of the thermal paste on the cpu.
- Ask to confirm that the cpu is not an ES (Engineering Sample) - is there a way to independtly check for this myself? Considering how many units they have, they should be coming from reputable stocks/businesses.
- Ask for the mounting rails / bay for an additional 3.5'' spinning hdd (if I leave the 1TB spinning hdd and get the ssd instead, which is another +$30).
- Ask for a discount using the 5% store discount code that I have received from the 1st (semi-failed) sale.
- Ask for a front fan mount (standard hp p/n?). Not sure if they would have such thing.
- Ask for the "Front RAM duct" plastic part. Not sure if they'll be able to honor that, or if it is really important for the front dimm 1...4 banks to not overheat.

Anything else that you would consider wise to ask about?

[MtothaJ]

---

@smihaila wrote:

---

@MtothaJ wrote:

---

---

To run the v2 CPU's you need the 2013 bootblock. There has been plenty written on this subject - feel free to browse the forum for more info.  

The E5-1650v2 has the advantage that it can be overclocked in the Z420 by using Intel XTU. You are still limited to a 130W TDP limit but the performance gains are still substantial especially when fully utilizing just 1-2 cores (as many programs do).

The E5-2650 v2 has locked multiplier so it doesnt benefit from the above, while the E5-1650 v1 - while multiplier unlocked - does not respond to any tweaking in XTU (core multiplier sliders are grayed out).

---

Thank you for this - considering your new info, yes, it does make sense to upgrade to E5-1650 v2 (even if comparing to E5-1650 v1 the 100 MHz higher base clock rate is not too much). And the ebay store is only asking for $30 more for this upgrade.

And regarding the 2013 bootblock, your intervention was pure telepathy - in sync with my similar finding on a web forum on tomshardware, I guote:

"-To determine if the Z420 can support the v2 CPUs, look in the F10 BIOS setup for the boot block date
=> If the Z420 has a boot block date of 12/28/2011, it supports only the v1 CPUs
=> If the Z420 has a boot block block of 03/06/2013, it supports both the v1 and v2 CPUs.
HP does not support updating the boot block. "

Such requirement couldn't be more than welcome. Because by doing the upgrade to the 1650 v2, I would have a double confirmation that the seller will definitely give me another used Z420, completely different than the one which they have sent originally (I'm not sure if they "mix and match" mobos and cpus, and prefer instead to pick up a completely different Z420 from the recycled stock. And move only the RAM around). I shall explicitly ask them to triple-check that the bios shows (a) the 2013 bootblock, (b) v2 suffix for the CPU, (c) Right memory assignemnts in the banks and the memory type.

Thanks a lot for all this great info! I'll ask them to go with 1650v2 upgd. And either replace the 1TB spinning HD with, or add on base of that, also a 256GB SSD drive. Because I have noticed that the 1TB 7200 rpm hdd (a Western Digital) was super-noisy - either because the original owner has put it thru lot of intensive use, or it came from somewhere else, or maybe this Z420 does not have too much sound proofing / rubber washers around bays and hdd screws etc.

Along with those 2 upgrades, I also have this in my list of notes to ask them about for the upcoming Monday Feb 26 2018 (this is when the returned pc arrives back to them):

- Ask to take care of the thermal paste on the cpu.
- Ask to confirm that the cpu is not an ES (Engineering Sample) - is there a way to independtly check for this myself? Considering how many units they have, they should be coming from reputable stocks/businesses.
- Ask for the mounting rails / bay for an additional 3.5'' spinning hdd (if I leave the 1TB spinning hdd and get the ssd instead, which is another +$30).
- Ask for a discount using the 5% store discount code that I have received from the 1st (semi-failed) sale.
- Ask for a front fan mount (standard hp p/n?). Not sure if they would have such thing.
- Ask for the "Front RAM duct" plastic part. Not sure if they'll be able to honor that, or if it is really important for the front dimm 1...4 banks to not overheat.

Anything else that you would consider wise to ask about?

---

Yes, in your case it makes perfect sense to get the 1650 v2 - this will guarantee you get a new machine with the newer boot block date, which will ensure compatibility with both v1 and v2 CPU's and guarantee a better resale value when you come to sell the machine at a later date. The other advantages of the v2 chips which come to mind is:

i) official support for PCIe 3.0 - the v1 chips also support this but it is not in the specs, so for instance with Nvidia graphics cards you need a patch to make sure it runs at PCIe 3.0 rather than PCIe 2.0 speed and

ii) support for 1866Hhz memory vs 1600 MHz of the v1.

THe front fan kit is definietely nice to have although can be expensive and hard to find at this point in time. In any case they can be easily retrofitted later on. HP part number is A2Z46AA

The front RAM duct cover from what I am aware doesn't do much for RAM temperatures (in fact quite the opposite). THe main purpose is to ensure that the CPU cooler does not suck in the warm air from the RAM slots - this part was usually fitted on machines which came with more RAM as standard and again - if you can find the part it can easily be added later.

Once thing to also consider is perhaps going for the Z620 v2 instead of the Z420 v2 - arguably it has a slightly better / nicer case design and  the cooling options come as standard.