So, I was busy with my HTPC trying to keep the power consumption as low as possible but doesn’t want to sacrifice the performance too much. At least it can handle 1080p 10bit video. I know that 4K is more future proof. However, the lack of 4K contents for now makes me think twice to purchase the parts needed, especially with my current budget which is quite tight.
After thinking too much, I think I should keep my older computer parts such as the rather old Gigabyte G41MT-S2 which I purchased on early 2011. The good thing with this motherboard is, it already use DDR3 memory. Although still limited to 1333 MHz. Better than DDR2 at least. But…! There is one problem though… With my current CPU, which is Intel Pentium E5800, the board can only run the memory at 800 MHz. Damn… 😦
This is not a big deal actually, but kinda bugging me because on higher bitrate 1080p 10bit video, the CPU can’t decode the video smoothly, even when clocked at 3.6 GHz. Overclocking it further is not a good option. The motherboard is a terrible overclocker and the CPU doesn’t like to be clocked real high. I did spend quite sometime trying to overclock the CPU to 4GHz with no avail. No matter what voltage I threw, the CPU can’t get stable. Other than that, overclocking is clearly not the solution because I was looking for the solution the keep the power consumption as low as possible. So… I give up on overclocking and decided to undervolt the CPU to reach lower power consumption.
The result of my undervolting experiment on Pentium E5800 is quite good although it was not smooth. The CPU can go as low as 0.996V and stay stable when clocked at 2.5 GHz. The power consumption is also quite good, going as low as 63 Watts on idle. However, the system is noticeably lag because I limit the clock speed at 1.2 GHz. At 2.5 GHz, it’s much more acceptable. But then again, I saw the price of Intel Core 2 Duo E8400 was very very low on a local computer store. So, I decided to purchase it and replace my aging Pentium E5800 with a more aging Core 2 Duo E8400. FYI, Pentium E5800 was released on late 2010 while Core 2 Duo E8400 was released on early 2008. Sounds stupid? Not really…
Intel Core 2 Duo E8400 (left) and Intel Pentium E5800 (right)
From the picture above, you can see the specification of the two.
Core 2 Duo E8400 : 3GHz/6M/1333
Pentium E5800 : 3.2GHz/2M/800
Why the hell I switch my CPU with the older and lower clocked one? One main reason, faster DDR3 Memory speed. 1333 MHz (on E8400) vs 800 MHz (on E5800). Other than that, I thought Pentium E5800 and Core 2 Duo E8400 are the same Wolfdale chip but Pentium E5800 comes with disable L2 Cache. I was wrong. This two chip are identical, but they are actually a slightly different design. Core 2 Duo E8400 uses the “full-fledged” Wolfdale core while Pentium E5800 uses Wolfdale-3M core (with 1M L2 Cache disabled) which is actually a smaller chip and slightly different than the full-fledged Wolfdale. Wolfdale is more powerful but also draw more power than Wolfdale-3M.
I learned that memory bandwidth was also important when I saw ASRock demonstrated the Beebox which is powered by Intel Celeron N3150. With single channel memory, the system lags when decoding 4K video, but with dual channel memory, the system can decode 4K video quite smoothly. I was not aiming at 4K though. I’m not even sure E8400 can handle it without lag and my Graphics Card doesn’t support 4K via HDMI.
So, how’s the result? Quite nice, but not everything is nice. First thing I noticed is E8400 can handle 1080p 10bit video without lag at 3 GHz. However, thepower consumption is noticeably higher, even higher than E5800 when slightly overclocked to 3.6 GHz. I don’t like this so I switch the E8400 with another E8400 (I bought two, one for me and one for my friend). The other E8400 draws slightly lower power and operates at noticeably lower temperature. It’s nice to see this CPU works just okay at 0.996V even when clocked at 3 GHz. So I decided to get lower to 0.944 and the CPU is now clocked at 2.5 GHz as well. With DDR3 memory running at 1333 MHz, performance on video playback is noticeably better than E5800. Thanks to the DDR3 memory, and probably due to the significantly larger L2 cache (6M vs 2M) on E8400 as well.
The not so nice thing is the overclocking. My motherboard refuse to boot at 400MHz FSB. So I can’t run the DDR3 Memory at 1600 MHz and I can’t really overclock the CPU. Second is clock speed. Basically, E8400 only runs at 2 GHz or 3 GHz. It doesn’t have any speed step between. But this one is not such a big deal. 😦
And about the Graphics Card, picking the old and weak Radeon HD 5450 is many hit and a bit miss. It can handle common 1080p 8bit videos but when deciding from Bluray disc directly using GPU Acceleration, the video feels kinda lag. Also, this GPU doesn’t support 4K output via HDMI. But… this is the lowest power consuming GPU and the cheapest GPU with Audio over HDMI my money can buy. I should forgive this two problems for now.
The specs for my HTPC should be :
|CPU||Intel Core 2 Duo E8400 at 2.5 GHz|
|RAM||2x 2GB G.SKILL Ripjaws DDR3 at 1,333 MHz CL 9-9-9-24|
|Graphics Card||XFX Radeon HD 5450 1GB DDR3|
|SSD||Kingston SSD Now V300 12GB|
|HDD||1x Western Digital 500GB WD5000AACS
1x Hitachi GST 3TB HDS723030BLE640 (damn that is a long model number)
1x Western Digital 6TB WD60EZRX
It won’t do any good for spec-demanding games but should be works just fine for web browsing and watching videos.