weak cooler after replacing CPU

[BurningSoul1]

I have replaced E5-2620 v4 with E5-1650v4. One has TDP 85W and another 140W. I run some CPU benchmarks to see how it goes after replace and discovered, that temperature of the CPU reached at its max. 85°C with E5-1650v4 and abt 60 with E5-2620v4. In idle state both have around 28-30°.I am aware of more heat generated by 1650v4. But that silly fan on cpu heatsink wont go faster under load as is usual with my previous desktop. I read it is issue on many stations and in BIOS it can be either ramped up or down. If I buy aftermarket cooling solution, i dont get it connected on MOBO, since it has 6 pins. how can i now solve this problem? installing additional suction fan on the heatsink from the other side of the heatsink (to pick up hot air and transport it away)?

to be honest, this syntetic test was using all 6/12 cores on 100% and this will not happen with games 

[BeemerBiker]

You will need a better cooling solution.  Even though many games use only one thread the game will share the core with another thread unless you disable hyperthreading.

This z640 fan has 6 pins ,  Here is another.  look at the pinout.

The top two pins are basically jumpers and connect to pin1 ground .  You could wire up your own adapter using a pair of jumpers and forming a Y bridge.

I do  not recommend this z640 adapter as there are no reviews and the jumpers are missing.  It is suspicious.  Every time you power up the BIOS may give a warning about the fan and ask you to press F1 to continue.  You could contact them and ask.  If it does work then possibly this cooler could be used as it needs 4 pins, not 6..

[SDH]

Are you running that Z640 with a single processor or with two? My guess is just one processor because the E5-1650 v4 can only run as one. The "riser" small motherboard that carries a second processor takes up so much space that HP could only fit in smaller heatsinks and sent out the Z640 with only the smaller type even if it was only running 1 processor. That second processor issue is never an issue in the Z440 workstations.

We here run our Z440 and our single-processor Z640 workstations with the larger Z440 stock heatsink. It has almost exactly double the cooling fin surface area of the smaller Z640 and Z620/Z420 workstation heatsinks, plus has 4 heat tubes including the two central ones that are especially large. See pic below. It also has the same 6-pin fan plug that fits on your motherboard's header perfectly. HP even uses that in a kit to add premium cooling to the Z4 G4 workstations when high heat processors are added (the kit includes a 6-to-5 pin special adapter for the header used on those motherboards which has a pin 3 to pin 5 jumper we've posted about here).

The reason this works is that the stainless-steel fittings over each of these different processor-family workstations is the same. It is the contact pinout on the motherboard beneath the fittings that changes from family to family. Thus, the same heatsink fits on all those. Search for 749554-001 on eBay... about $20.00. Here's the undersurface. Then take a look at "Z640 heatsink" to see the smaller size you currently are using.

Edit: BeemerBiker got his post in while I was typing... He is correct that adapter from modDIY is the wrong one. They make several others including one with the correct mod to get RPM sense signals over from pin 3 to pin 5 for the Z4 G4 kit to work. They copied the one from HP. You don't have that issue with your Z640. Nonsequiter posted on using that kit concept and this Z440 big heatsink on a Z420 he souped up with a greater-than-140W max TDP processor. I don't think you'll see his issue in your Z640 with your single processor, however. Please update us on how it goes if you use the easy fix of just a heatsink swap with no adapter. I can get you the part number from modDIY if you need that special one... their site is hard to search. I have one of their sleeved versions of the Z4 G4... takes under 2 weeks to get from China.

Note in the pic that there are two total small front and rear centerline mounting screws... I like this type best. Some other ones with same part number have those 2 small screws on one side only which I think makes the attachment of the top box to the baseplate a bit weaker.

[BurningSoul1]

I looked now on the cooler and it is actually 749596-001. What I dont understand is why it is not increasing speed of the fan in order to blow away hot air. 

to build my own adapter ( I found there actually this adapter with wirings PC CPU Fan 6 Pin Female to Standard 4 Pin PWM Male Cable Adapter for HP - MODDIY) I need to know what kind of 6-pin connector it is. can i buy it somewhere without wires?  Or maybe buy another naked 6-pin cpu fan, cut it and connect it with another 4-pin fan?

Or just to know how to even manually change speed of the fan from windows. i think this fan, running on higher RPM than what it is, 1000RPM? can fullfill this job as well.

[SDH]

No... that is not the right one either. I'll go dig out my info on the correct part number and edit it into this post shortly.

EDIT:  Here's the link for the pin 3 to pin 5 adapter from modDIY:

https://www.moddiy.com/products/HP-computer-CPU-Fan-6-Pin-Male-to-5-Pin-Female-Cable-Fan-Conn-Adapte...

I have not run up against this issue before so you'll be helping others by figuring this out. I'd try the bigger Z440 heatsink in your Z640 first and see if that solves your problem by itself.

Here's a good added post to review:

https://h30434.www3.hp.com/t5/Business-PCs-Workstations-and-Point-of-Sale-Systems/Z4-G4-912-Error-wo...

[SDH]

I have not found the threshold max TDP for a processor that triggers the motherboard's demand for a "Premium" cooling solution on the HP motherboards. In the past we used to think there were only "Mainstream" and "Performance" CPU coolers. Then came the discovery that HP has the special kit that uses the big Z440 6-pin-fan-plug and the HP special adapter that feeds pin-3 sense data over to pin 5 of the Z4 G4 workstations running high wattage processors.

Then more recently came the discovery by forum member NonSequitur777 that in a Z420 he was souping up with a high wattage processor he could work around a demand to use water cooling with the same basic trick... get RPM sense signals from pin-3 jumpered over to pin-5 in that Z420. He made the equivalent of the HP and the copy modDIY adapter from scratch to do that, and it fixed his problem. Kudos to him.

I currently have no idea whether use of the special pin-3-to-pin-5 modDIY adapter would accomplish that in your Z640 and let the motherboard's automatic control system raise and lower fan speeds as needed. Certainly, if you just use that large cooling fin surface area heatsink from the Z440 it will give your processor significantly better cooling (and that might be all that you want and need). The modDIY adapter I got to use with that Z440 heatsink in my Z4 G4 was sheathed (not needed at all), very high quality, shipped from China where they make them, took a bit under 2 weeks to arrive, and I could pay for it via PayPal. More recently when I wanted another and using PayPal with them was not working. Maybe that was their way to reduce total cost and thus not raise pricing? This is a long-term good company.

Your new processor is a max 140W TDP one so what you report may be another issue altogether. That TDP does not fall into the usual category of what would demand a "Premium" heatsink/fan or water cooling. I now think that trigger threshold is at or over 145W max TDP. Those big Z440 heatsinks are so reasonably priced, recycled from eBay, that I upgrade to them on all our single-processor Zx20 and Zx40 builds unless they're running a wimpy processor.