Dell Workstation Owners Club

[lexluthermiester]

But The RDIMM question has merit.

The more I read about systems that are socket 1366 based, some of which can use RDIMMS, the more it seems likely that this may be doable. DDR3 RDIMMS are cheap right now. Thinking I might try this with 1rank and 2rank modules and report the results.

 

[Retrorockit]

There was another post at OCN from a regular there who confirms 16GB RDIMMs on some X58 MB for 96GB RAM. Says not all support it. Of course no one over there is going to try it on a T3500.

 

[lexluthermiester]

There was another post at OCN from a regular there who confirms 16GB RDIMMs on some X58 MB for 96GB RAM. Says not all support it. Of course no one over there is going to try it on a T3500.

That's a shame. I'm betting it'll work.

 

[Retrorockit]

The native ECC suppport is a big plus. It removes one variable. The memory controller on the CPU is outside of Dells control. Since it requires another mod (5600 series CPU ) to try it, I doubt if it was anticipated and intentionally blocked. I think the odds are pretty good. Maybe try it single/dual channel before going all in?

 

[ManGupta]

There was another post at OCN from a regular there who confirms 16GB RDIMMs on some X58 MB for 96GB RAM. Says not all support it. Of course no one over there is going to try it on a T3500.

Actually internet is full of confusing findings ....... some say RDIMMs support is just based on Memory Controller integrated in the processor ....... whereas some say its combination of Memory Controller integrated in the processor plus the chipset on the MB.

I tried figuring some clues on the Intel site ......... but Intel Site ...... in the Spec for its various processors specifies whether Memory support for the particular processor supports ECC/Non ECC but completely avoids mentioning anything about RDIMM/UDIMM ..... which leads to speculation that it may not be just a matter of MC integrated on Processor but also combi of Chipset.

BUT ...... everything is just an SPECULATION .... that's it.

https://ark.intel.com/products/4791...X5680-12M-Cache-3-33-GHz-6-40-GT-s-Intel-QPI-

 

[Retrorockit]

I think the phrase dependent on memory type says it all. UDIMMs end at 8GB Modules. So up to 48GB for each CPU is about it. RDIMMs would be required for 96GB and up capacity. They don't specify RDIMMs because it supports both types. This makes them interchangeable at the CPU level on the high capacity CPUs.

 

[lexluthermiester]

Since it requires another mod (5600 series CPU ) to try it

Curious what you mean? Most of the T3500's I seen come with Xeon's stock from Dell..

 

[ManGupta]

That's a shame. I'm betting it'll work.

The native ECC suppport is a big plus. It removes one variable. The memory controller on the CPU is outside of Dells control. Since it requires another mod (5600 series CPU ) to try it, I doubt if it was anticipated and intentionally blocked. I think the odds are pretty good. Maybe try it single/dual channel before going all in?

Actually internet is full of confusing findings ....... some say RDIMMs support is just based on Memory Controller integrated in the processor ....... whereas some say its combination of Memory Controller integrated in the processor plus the chipset on the MB.

I tried figuring some clues on the Intel site ......... but Intel Site ...... in the Spec for its various processors specifies whether Memory support for the particular processor supports ECC/Non ECC but completely avoids mentioning anything about RDIMM/UDIMM ..... which leads to speculation that it may not be just a matter of MC integrated on Processor but also combi of Chipset.

BUT ...... everything is just an SPECULATION .... that's it.
View attachment 110264

https://ark.intel.com/products/4791...X5680-12M-Cache-3-33-GHz-6-40-GT-s-Intel-QPI-

I think the phrase dependent on memory type says it all. UDIMMs end at 8GB Modules. So up to 48GB for each CPU is about it. RDIMMs would be required for 96GB and up capacity. They don't specify RDIMMs because it supports both types. This makes them interchangeable at the CPU level on the high capacity CPUs.

UPDATE

Found something new ........

Just ran software Sissoftware Sandra ...... In Tab Hardware >> Mainboard ---- this software is displaying that my system supports ECC DIMM Registered DDR3 ........ Wow .... !

 

[Retrorockit]

Curious what you mean? Most of the T3500's I seen come with Xeon's stock from Dell..

You probably have much more experience with virgin Dell T3500s than I do. Do they come with the 2 QPI X5500,X5600 series (which I would consider a mod)? Or the single CPU X3500,X3600,W3500,W3600 Xeons that I would expect.
This would align with the 24GB RAM limit and UDIMM support better.

@ ManGupta
I also noticed that it lists 48GB Max. RAM support, which is good and sort of expected. But if true to some extent defeats the purpose of an RDIMM mod. Of course lower cost is a factor. If the chipset has a 48GB limit you can get there nowadays with Udimms. So RDIMM may be supported but just up to the "normal" 48GB RAM chipset capacity.
I'm guessing the X5000 series Xeons may bring RDIMM support, but the chipset will limit it to 48GB. It may be a way to get 48GB on the cheap, and with TS overclocking you don't need fancy boutique RAM anyway.
Thank you for that information.

 

[Susquehannock]

RDIMMs. Yeah, I wish. Can only speak for these IBM 8gb 2Rx4 1.35v modules so far. Work flawlessly in my T5500 board.
No go in the T3500 at any configuration. Only get "S8" error. BIOS won't even complete POST sequence.

Had my finger on pulse of DDR3 RAM prices for a while. Wide fluctuations on server modules. RDIMM are about 40-50% less than UDIMM and non-ECC modules right now. RDIMMs I linked above just dropped another $5 today as matter of fact. Down to $22.65.

When I bought the above, single rank modules were still quite expensive. Price has dropped considerably since. Especially 1600mhz units. These are worth looking into.

Why don't we see a lot of people running RDIMM in X58 boards? Price changes perhaps. Same part #49Y1415
IBM modules as above were over $300 at release time.

Wondering why the T3500 manual makes no mention of RDIMM compatibility yet the T5500 does.

 

[Retrorockit]

You didn't specify which CPU you tested with in the T3500. That may be the key factor. The memory controller on the CPU in the 5000 series Xeons may bring RDIMM suppport.
T3500+3000 series Xeons= UDIMM only support
T5500+5000 series Xeons=RDIMM support, and probaly UDIMM also. ( won't run 3000 series Xeons)
T3500+5000 series xeons= ?????
I don't think the T3500 manual entertains running the 2QPI Xeon 5000 series CPUs.

 

[lexluthermiester]

Do they come with the 2 QPI X5500,X5600 series (which I would consider a mod)?

That would be yes. They did/do often have the X5600 dual QPI models in them.

No go in the T3500 at any configuration. Only get "S8" error. BIOS won't even complete POST sequence.

Was that with 1R or 2R RDIMMS?

Wondering why the T3500 manual makes no mention of RDIMM compatibility yet the T5500 does.

Maybe because there is a factor of the chipset compatibility after all..

 

[Retrorockit]

OK two strikes against this working.
T3500 came with X5000 Xeons so it's not a "mod".
Suspehannock tried it and it didn't work. CPU unspecified? Assorted types of RDIMM a possible factor also.
I've had reports from OCN of X58 running RDIMMs. Seems to vary form one MB to another.

There may be a pin in the RAM socket that reads the type installed. I came across that in the manual for the MSI X58 Alienware board I have.

When you install incorrect memory module (the SA2-pin of the memory module connects to Ground) in the DIMM_C0/C1, the LED beside DIMM_C0 will light red color to remind you. The position of the LED is shown as below. Double confirm with your memory module vender for the third channelsupports.
So it may even be a hardwired prevention.

 

[Susquehannock]

You didn't specify which CPU you tested with in the T3500. That may be the key factor. The memory controller on the CPU in the 5000 series Xeons may bring RDIMM suppport.
T3500+3000 series Xeons= UDIMM only support
T5500+5000 series Xeons=RDIMM support, and probaly UDIMM also. ( won't run 3000 series Xeons)
T3500+5000 series xeons= ?????
I don't think the T3500 manual entertains running the 2QPI Xeon 5000 series CPUs.

[edit] CPU = W3680.

Yes. Meant to mention that. Only tried those IBM modules in T3500 in my signature so far. Since it is a single QPI chip was considering whether that was a factor. System runs so well with overclocked W3680 that I have been reluctant to go back to quad core and drop a X5687 to try it. Found X5690 at good deal so may try that once it arrives just to confirm if QPI is a factor.

 

[Retrorockit]

Can't blame you for that. I would hate to undo that setup too.
The report at OCN is 16GB RDIMM working and 96GB on X58 is possible due to it. But no specific examples were given.

 

[ManGupta]

Here is the Pinout Mod required .... You need to swap wire No 1 with Wire No 3 .....
image host

Dell wont let you customize ...... even small things like CPU Fan / case fans.

Did the pinout mods to add CPU Fan to CPU Heat Sink ....... But just when I tried to insert the modded 4 Pin Fan Connector (after swapping Wire No 1 with Wire no 3, as explained in my earlier post) ...............

BUT ....... Dell is Dell .....

The Dell has Made its 5-Pin Fan Header so thin that No standard Fan Connector can be inserted in ....... making all my Pinout Mod efforts useless ......

So instead I had to connect Fan directly to the Power Unit to run it ...... but in this way PWM will not function and fans will run at full speed.

But running fan at full speed always means fan will get depreciated sooner that its rated duration.
So I decided I will not use expensive high quality Noctura Fans but Cheap Generic Fans (but with CFM at least 67% of that of Noctura Fans).
That way whenever fan will get worn out in 2-3 years I will just throw them away and get new ones.

In total I planed to add 5 Fans .... (2 80mm Exhaust fans at the back, 1 small 50 mm fan to be mounted on Northbridge Heatsink and 2 92 mm Fans to be mounted on CPU Heat Sink in Push-Pull Config). However T3500 525 Watt PSU do not have sufficient number of unused connectors to power 5 extra fans. So I needed some mods here also.

Finally ......

I got all my mods done and the CPU Temps are down from 56 C to 25 C (idle. (Note: In India ambient temps are high(over 30C) ..... so even at idle temps were around 56 C). After my 5 Fan Mod temp is now 25 C idle and 67 C on full load during stress testing. Earlier during stress testing temp went over 100 C leading to throttling and lowering of clock speed, now no throttling as temp never goes over 67 C even during stress test. These figures may not be impressive but trust me these are really good considering that in India Temps are really very hot and also I do not use air conditioners.

draw power from the floppy wires with connector cut off. Who uses floppies anymore?
View attachment 101850

You need not cut floppy connector off ................ you can just use a compass needle to take out from connector the yellow and black wire and leave aside the remaining portion of Floppy Connector.

 

[Retrorockit]

I just splice the Dell connector onto the new fan. But then I have a pile of old Dell fans sitting around. P041K cooler has a couple more heatpipes. N764D is a little taller but has twice as many pipes and a 5 pin cable, but a generic ATX type mounting bracket. If you have hotter air for cooling then I guess you need a lot more of it to get the job done.
The T5500 MB D883F has nice active chipset cooling. The MB swaps with the T3500 but runs 5500/5600 series Xeons only. The MB components won't allow just a cooler swap.
Bu those are nice mods and if it solves your problem that's great. I'm just a hardware junky and have all of this stuff sitting around.

 

[ManGupta]

If you have hotter air for cooling then I guess you need a lot more of it to get the job done.

Any more suggestions ..... ?? ... Please.

 

[Retrorockit]

I always start my cooling mods right at he CPU interface. I do lapping in an overclock situation and it helps. You can also run a load test like Prime 95 and use Throttlestop to undervolt the CPU. How this is done on X58 I'm not sure . But this can lower temperatures considerably. Your situation is unique. Air cooling and water loops can only try and approach ambient temperature which in your case is pretty high. My Optiplex 380 X5470 running Prime95 ran 68*C. @ 1.25V. it now runs 62*C 2 1.1125V. If i speed up the fan it can go much lower. I've had Prime 95 @58*C with just the 1 stock optiplex fan. I prefer 1 big fan with the air ducted to the CPU cooler,but that;s the way BTX is. While writing this I just stuck the big fan I installed on page 8 of the overcocking thread in my optiplex 380, and at idle I'm running Prime 95 small FFTs @ 57*C. The CPU fan i replaced was the Foxconn .9A. the same as T3500 uses. Since it never speeds up I'm not too concerned about the 1.8A. rating. This may not apply to your situation. I had to pull the CPU cooler up to remove the old fan so there's probably air in the thermal paste right now. Actually this heatsink is lapped because most of mine are, but the CPU isn't. I have another BTX cooler T9303 that cools better than this one, and another TJ258 much better than that. But obviously not needed in this computer. My Ambient is 78*F. The big fan by itself is often just the same size as the 120mm with it's housing. In the BTX mini tower I just velcro it in, and tape th seams. i didn't even bother to do that this time.
The fan mod on page 8 with the Thermalright macho 120 was basically bolt in except for accurately locating the holes in the cover. The fan mod required drilling 1 small hole and glueing a nut over it.
I just kicked the big fan up to 2500RPM and it's running small FFTs @ 52*C. $10 heatsink and a $15 fan in a $20 Optiplex. Thta's the hottest core 2 of them are at 47* C.
I guess this will be my burn in test for the Xeon swap.

 

[ManGupta]

Friends,

I just realized that The T3500 (Refub) which I bought do not have the small Aluminium VRM Heat Sink (just adjacent to CPU Heatsink) on it.

I request all T3500 / T5500 / T7500 owners to check and confirm whether this small VRM heatsink (just adjacent to CPU Heatsink) is there on there system or not.

The seller from whom I bought claims that this particular workstation was shipped by dell like this only and if dell thought necessary only then it would have had added the heatsink, but merely having provision for including the VRM Heatsink does not necessary mean that Dell shipped that system with Heatsink included.

Please check if your system have been also with or without it and confirm.

Below is picture of VRM HS as taken from Dell T3500 Service Mannual and the other picture below it is the picture of my system.

 

[lexluthermiester]

The seller from whom I bought claims that this particular workstation was shipped by dell like this

This is correct. The models of T3500 which shipped from Dell with the heatsinks on the VRM's were the early models which had less efficient VRM parts. After the first batch or T3500's were made, the VRM's used were more efficient and didn't get nearly as hot, thus did not need cooling. If you're worried about them heating up, you can always buy a heatsink kit. I have two T3500's here, one with a X5680 and one with an X5675. Neither of them have heatsinks on the VRM's. You'll be fine.

 

[ManGupta]

This is correct. The models of T3500 which shipped from Dell with the heatsinks on the VRM's were the early models which had less efficient VRM parts. After the first batch or T3500's were made, the VRM's used were more efficient and didn't get nearly as hot, thus did not need cooling. If you're worried about them heating up, you can always buy a heatsink kit. I have two T3500's here, one with a X5680 and one with an X5675. Neither of them have heatsinks on the VRM's. You'll be fine.

Thanks for Confirmation ....

Just for the sake of info ....... Does this thing applies to T5500 / T7500 as well .. ?

 

[lexluthermiester]

Thanks for Confirmation ....

Just for the sake of info ....... Does this thing applies to T5500 / T7500 as well .. ?

As a general rule, it applies to most Dell systems unless there are high wattage CPU's used in the model being sold.

 

[ManGupta]

Friends,

There is a small Internal Speaker mounted on the front of dell T3500 which is directly connected to the motherboard with a 5-pin header near CMOS battery. Is this small Internal Speaker for giving Diagnostics Beep Codes in case system does not boots or is it for normal audio ?

 

[Retrorockit]

Be careful putting heatsinks on the VRM in these. There are components in between the MOSFETs that are sticking up in the way of doing that.
I took the Scythe NinJa off of the T5500 MB and tried the Dell 0P041K cooler. The mounting bolts are all wrong, but the size and bolt pattern are correct. 50% more heat pipes and comes with a fan. Male to male bolts is the issue. I don't have an original heatsink to try the old hardware. But this is the cooler I would go to on a t3500. The fins are folded down on the sides to form a duct so all the air from the fan passes over the heatpipes.
A little more on fans for ManGupta. There are variable speed fans that are not PWM. They have a blue thermistor sticking up from the motor in the back. They vary speed based on the temperature of the air passing through them. This may be useful in your environment. The thermistor is a resistor, and if you add a resistance between the legs it will be a resistor in parallel which willl make the motor run faster. Normally used as an exhaust fan. Some Nidec Beta V TA350DC comes like this. You can see the sensor here.
https://www.aliexpress.com/item/Fre...Thermal-Sensor-Fan-12V-1-8A-3/1956098195.html
This is a 38mm thick fan. This lets fans move more air without a lot of RPM. I always prefer these over 25mm thick fans.
The cooling mods I posted above would apply to the T3400 directly because it's a classic BTX. The T3500 is a modified BTX, but the cooling works on the same principles. 1 powerful fan, and good control of airflow. But instead of a duct they use the HDD tray, the RAM shroud, and the case and cover to form one around the heatsink. 100*F. ambient is an interesting problem. I think my BTX overclocking cooling mods could handle that easily. Too bad I wasn't asked this a week a go when I had my 65W Q9505S quad core in there. I might have gotten Prime 95 running in the high 40s.
But I did the BIOS mod so it's probably not supported anymore. The temperatures I got above on the X5470 would represent a 10% overclock on a Q9650 CPU.