TT Big Thyphoon VX and Scythe Ninja are those fat fat heatsink...

Yes, they do work well...
But, if u're going to use those heatsink with HR-05 northbridge heatsink, u might have a clearance problem...

Let's discuss...
As u're going to use it on DS3, it's on LGA775 platform...

LGA775 Platform have one good point though...
It is, you can fit you're heatsink on any way you've wanted...

And for that reason, i suggest you get a heatsink with thin thin body...

Such as Thermalright Ultra 120 & Thermalright HR-01 or CoolerMaster Hyper LX

Those are good good heatsink...
Infact, HR-01 are known for it's performance that is on par with Scythe Ninja on fanless...

Dunno about Coolermaster Hyper LX though...

As u're going to use HR-05 on the northbridge, i suggest you take either this two heatsink:

Thermalright HR-01
Or
Thermalright Ultra 120...

[Don't blame me for being a fanatic on thermalright guys ]

This two heatsink are thin and can be mounted on any way...
Either to make the fan go straight to the rear exhaust fan, or to blow it straight to PSU...

You could use you're own imagination...

This way, you could deal with the clearance problem of using that HR-05 with those fat fat heatsink...

So go get you'reself those thin thin but high heatsinks...