Wednesday, July 4, 2012

The need and pitfalls of RAM Cooler installations

The concept of air cooling can be extended from a CPU to other components in the motherboard like RAM, PCI/PCI Express cards, etc. You need a heatsink and a fan to dissipate heat. You can see this in a graphic card also.

The RAM modules are an important target. From my C programming background, I understand the best way to speed up any routine or algorithm is to try and make it CPU bound (eliminate frequent memory lookups) and also achieve some locality of space and time of both data and instructions (in  other words make full use of CPU's cache memory). This is a low-level programming craft and most applications in my domain are written in high level languages like C/C++ , where developers are ignorant of this, or do it only for some key routines and not whole critical path code (forget the whole code). Worse many believe that design optimizations give better results and therefore no need to do low level code tuning. 

RESULT: A lot of memory accesses in any code(application). With multi-threaded applications and the gap between CPU speed and DRAM speed, this means very frequent DRAM access translating into heat buildup in the DIMM modules.

My Gskill RipJaws X had heatsink fins. So i extended the CPU cooler concept by looking at a RAM cooler fan and I got one from Gskill in Turbulence II with lovely blue LED fans. Corsair and Patriot also make  this cooler.  Easy to mount and dismount and takes power from a molex cable which can be connected to the PSU. However there are two things I want to warn others about




1. One side of the Turbulence II touches the Fan on the CPU air cooler since the DIMM slots are next to the CPU on my motherboard (Asus P8Z68-V PRO/GEN3). I see most Mobos have this arrangement. So it will block block some airflow into the cooler. And I had to shift the DIMM cooler towards one side to make sure it fit. That's where the second problem started
2. The base of the RAM Cooler's holders fits on the white DIMM slot levers (which we pull down to eject DIMMs). When I shifted the RAM cooler it covered the USB 3.0 header on my motherboard for the front USB 3.0 slots in HAF-X. Since I did not have a USB 3.0 device as of today, I disconnected the front USB 3.0 header as of now. It is the only open issue and I cannot find a way out except take a plier and alter the RAM cooler's holder

So my general opinion is that the co-operation between Motherboard manufactures, Air cooler makers and DIMM makers need to increase and they need to define some dimension, spacing and layout guidelines which will make CPU coolers, DIMMs and RAM coolers more compatible with each other. If I need a USB 3.0 front port any time in future, I have no option but to remove this Gskill RAM cooler or install one from Corsair (which I suspect may fit based on the pictures of it) or just use my trusty plier.

As a general rule, now I feel that whatever we mount on the Mobo (except normal sized PCI/PCIe cards), must be done outside the case at the time of purchase to check compatibility or have a return policy




1 comment:

Unknown said...

recently I lost one of the fans on the Gskill turbulence and replaced it with a Corsair CMX-AF1. And this one no longer blocks the USB 3.0 header on my mobo. The Kingston and patriot ones also look like they will fit fine. So its up to gskill to follow the best practice and follow similar design as corsair, patriot and kingston