Sapphire has decided to go with a dual-slot fan design instead of the reference design that has been making the rounds from AMD. Obviously, the manufacturer is targeting a different group of users with its Radeon HD 6670, with a seemingly buffed up cooler from Arctic Cooling. This is one card that's not for the HTPC market but it's your choice to use it if you can fit this in your intended system. Aside from the non-standard cooler, this Sapphire card comes with the standard clock speeds, which is 800MHz for the core and 4000MHz DDR for the 1GB GDDR5 memory.
The SRP for the Radeon HD 6670 may be US$99, but we found the Sapphire going for around US$97 at online retailers. Considering its third-party cooler, it does seem like a decent deal.
HIS meanwhile, has decided to focus on the low-power and low TDP aspect of the Turks GPU and has outfitted its Radeon HD 6570 with a passive cooler. While the rear bracket may be a single-slot, the fins on this passive heatsink effectively takes up another slot besides the graphics card. So, you'll have to ensure that there's sufficient space for this graphics card. Unlike the reference design, which is low-profile, this is a full sized (height-wise), albeit short card.
The clock speeds are standard too, with its 650MHz core complemented by an effective memory frequency of 4000MHz with GDDR5 memory. Take note that HIS has a similarly passively cooled DDR3 version of the Radeon HD 6570 with 1GB of memory. That version uses a truly single-slot passive cooler, so it's an alternative if chassis space is an issue. We weren't able to get the retail price for this HIS Silence, but we expect the price to be within the SRP of US$79, with perhaps a slight premium for the passive cooling.
The Radeon HD 6450 also gets the passive cooling treatment, distinguishing it from the reference design. We doubt that HIS is the only vendor taking this approach, as the low-profile, low-power nature of the Radeon HD 6450 makes it most appropriate for HTPC and quiet desktop configurations. With the exception of the heatsink, this HIS card is identical to the typical Radeon HD 6450, though this card is clocked at the lowest end of the spectrum for the Radeon HD 6450.
If you can recall from our specs listing, the Radeon HD 6450 can be clocked from between 625MHz to 800MHz for the core and it can come with a DDR3 or GDDR5 memory config. While HIS has gone with 1GB of GDDR5 memory, it is at a relatively slower 800MHz (or 3200MHz DDR equivalent) and the core clock of 625MHz is at the lowest possible spectrum. That should lower any expectations that you may have for this card, though we'll also be overclocking it later to find out the difference in performance.