CPU vs GPU Video Encoding with Sony Vegas Movie Studio HD Platinum 11

A unbelievably long title for a rather long article, nevertheless the title is justified and you shouldn’t be concerned about it. 😛 Let’s jump to the details, shall we?

Have you seen the video in the last article? (AMD APU Media Launch) – notice how the video now has an intro and ending? 🙂 I finally took the leap and acquired a proper video editing software, and now it’ll be use for all upcoming benchmarks.

Since the software supports GPU acceleration, I thought I’d give my existing processors and GPU a spin. (AMD Athlon X3 425 and Phenom II X6 1100T will be added, some other time).

The Contenders

3 CPUs in this test, with the i5-2500K overclocked, just for lulz.

CPU	Clock	Cache
Intel Core i3-2100	3.1Ghz (31×100)	4MB
Intel Core i5-2500K	3.3Ghz (33×100)	4MB
Intel Core i5-2500K Overclocked	4.0Ghz (40×100)	6MB
Intel Mobile Core i7-2630QM	2.0Ghz (20×100)	6MB
AMD A8-3850	2.9Ghz (29×100)	4MB
AMD Phenom II X6 1100T	3.3Ghz (33×100)	9MB

2 GPUs added to the fray.

GPU	Core	Mem	Shader	Shader Qty
Palit GTS 450 1GB GDDR3	783Mhz	700Mhz	1566Mhz	192
Leadtek GTX 460 1GB GDDR5 OC	725Mhz	900Mhz	1450Mhz	336

Benchmark

The test is simple – to convert this video in its original Full HD (1080p) form into 720p

Audio: 128 Kbps, 48,000 Hz, 32 Bit, Stereo, AAC
Video: 25 fps, 1280×720 Progressive, YUV, 8 Mbps

Here’s the result from the benchmark, I’ve sorted them (based on completion speed) for ease of viewing.

CPU	Time Taken	Cost (MYR)	Value
Intel Core i5-2500K OC	258 seconds	650
Intel Core i5-2500K	294 seconds	600
AMD Phenom II X6 1100T	326 seconds	710
Leadtek GTX 460 1GB GDDR5 OC	330 seconds	750
Intel Core i3-2100	454 seconds	350
AMD A8-3850	473 seconds	470
Intel Mobile Core i7-2630QM	518 seconds	N/A	N/A
Palit GTS 450 1GB GDDR3	618 seconds	330

Note that I’ve also added a COST and VALUE column. The numbers under the VALUE column is derived by dividing the time taken with cost. Higher the number indicates better the value for money. While speed is important, I think studying the value makes the benchmark more informative.

*Just realized the VALUE part doesn’t seem quite right. Still wondering what formula would be good.

I thought of adding the power consumption part but I don’t think it’s necessary, since the video encoding time doesn’t take all that long and the difference in your electricity bill wouldn’t be significant. Let’s back track to the discussion on value.

*The GTX 460 is a previous generation card which is practically non-existent in the market now. The closest you can get, in terms of number of CUDA cores, is the GTX 560 that retails at around RM 750. The stock speed i5’s cost is based on the non-K version.

I Don’t Have A Computer Yet

Then getting the Intel Core i3-2100 and pair it with the cheapest H61 board is the best option, low cost and pretty decent encoding speed. If you have budget to stretch then go for the Core i5-2500 (non K). You could go for the i5-2500K for overclocking but you’ll also be spending on a P67 / Z68 board that costs more, that lowers the value number (*the value figures in the table does not factor motherboard cost) plus you’ll need to muster the courage to enter the OVERCLOCKING territory (it’s not that bad, really).

I Already Have a Computer BUT……

You could ….

a) change the system (actually la, this one is no different from the above – buy a new system! You can sell off your old parts to reduce overall cost)

b) upgrade the processor – the easiest path as long as your existing motherboard supports the processor intended.

c) upgrade the graphic card – this is the path to take if upgrading the system is not an option and you’re stuck with a motherboard that doesn’t support those better processors. That said, this course of action requires you make sure your power supply is capable of handling the graphic card. Graphic cards using the nVidia GTX 560 GPU are great BUT they consume quite some power when on full load.

As you can see, either path incurs some cost. If you’re not doing video encoding that often, you could just bear with what you have. If you’re using processors like AMD Athlon X4, AMD Phenom X4, Intel Core 2 Quad, Intel Core i3 / i5 (previous generation), it’s quite likely your system’s performance is still faster than the GTS 450 in this test, and would hover around (or even beat) that of the A8 and i3.

Conclusion

So there ya have it, a comparison between CPU and GPU. 🙂 I look forward to add the X3 and X6 into the scores above for a more detailed comparison. It’s too bad the GTX 580 review unit has left goldfries HQ if not I would’ve included it into the comparison.

Keep in mind that the “course of action” points are just…. POINTS! You need to keep in mind the overall cost of upgrade.

For example, RM 1,000 could be spent on a new PSU and a GTX 560 – this path makes your machine a nice gaming rig too! Alternatively if you’re not into computer gaming, that RM 900 could get you an i5-2500 with H61 board and 4GB RAM.