Info: AviSynth and VirtualDub - speed improvement

_,,,^..^,,,_ said:

 

So, it seems that AviSynth and/or VirtualDub DO USE GPU power too, or the old GPU simply slowed down the CPU speed?

I know that some plugins can take advantage of GPU. I have an nVidia GeForce GTX 570Ti and it does make some difference to processing video. Modern graphics cards are capable of assisting the CPU with processing however, as I think they're mostly OpenCL capable nowadays. I still think you're better off spending the extra on a higher-powered CPU than faster graphics card as that will definitely make more difference with AviSynth and VirtualDub.

If someone had some similar experience, please post here... if only I knew this, I would have replaced my old video card before... years before!

I have had great boosts with certain CUDA-enabled applications (Premiere Pro exports in about half the time), but I cannot say I noticed a speed difference with Avisynth, but then again my last GPU was pretty efficient too. I guess if depends on the kind of plugins you are using. There is an option in VirtualDub that enables GPU acceleration. Perhaps that might have something to do with it.

My other guess is that you may have simply freed up resources by getting a better GPU. 256MB is not a lot of memory for a GPU now, so I'm guessing it wasn't too powerful. There are much better performance gains made by getting a faster CPU/RAM/Storage combination. RAID and/or SSD's combined with a powerful CPU will get you better performance boosts than a GPU can provide in Avisynth.

The Intel i7's appear to be the dog's doo-dahs at the moment. Intel has actually crippled some of the features on the i7's with unlocked multipliers because they can be pushed to match the Xeon CPU's for a fraction of the cost.

_,,,^..^,,,_ said:

I don't want to buy new PCs, as my three Sony VGX-XL systems are really beautiful "vintage" computers, still today with very good qualities that cannot be found on normal PC without a quite big budget... so, no "fancy" Intel I7!

I both agree and disagree with you here. I don't buy new PC's either, nor do I like doing so. Loads of bundled and unnecessary software, limited upgrade options due to the case/motherboard designs... no thanks!

What are these qualities it has? I find it hard to believe that a superior (contemporary) system would cost more than one of those systems brand new, which makes me intrigued as to what these features are that these systems have?

But, a Core 2 Quad Q6700 at 2.67GHz (the best CPU that Sony's motherboard and PSU could handle, and with no overclock, I'm sorry to admit) will be a huge improvement in speed.

It should be fairly cheap too, although you might have to shop around if you want a new one because LGA775 CPU's are becoming hard to find. I'd try to avoid used processors that have been over-clocked if you can as its possible the life of the CPU may have been shortened if it wasn't cooled adequately.

You should absolutely see a big improvement in speed over the Core2Duo without overclocking, and it wouldn't be recommended to overclock your systems either due to the case design.

I'm aware of no further speed boost by upgrading the GPU, but as the other two old videocards are dead, I think a better GPU than a "simple and honest" HD 5450 will give some modest speed improvement - after all, as I should replace them, I'll go for the best it could fit, e.g. GT 640 2GB or HD 7750 (1 or 2 GB).

If it is a case of the speed being higher because the newer GPU is leaving more resources free, then there's no guarantee that an even faster card will make a difference. The performance gain could be so small it would be out-weighed by the cost.

I was also aware of the CUDA related things, but I was surprised that an AMD Radeon could improve avisynth/virtualdub speed too!

DXVA and OpenCL are available on both AMD and nVidia cards and have been for some time, and I haven't found many free applications that support CUDA, but there are certainly more that support DXVA. CUDA has no effect on Avisynth/VirtualDub, but I don't know if DXVA does, either.

The fact that there are GPU-specific plugins available for Avisynth inclines me to believe it has no built-in 'default' use for a GPU. As usual this is just postulating, I have no technical evidence for this. ;)

About SSD and/or RAID: I could do both, but after I will upgrade CPU and GPU, I think the speed boost will be relatively small (5%? 10%?) - a RAM booster maybe could be a cheap alternative with comparable results, what do you think?

Admittedly, in terms of processing speed, it won't make much (if any) difference with an SSD or RAID setup, but the benefits are there when transferring files, capturing uncompressed at higher resolutions, or processing very 'light' scripts. A RAID 0 array of two hard drives, in the most basic terms, 'doubles' the access speed; the actual improvements at full speed are probably around 40%, in my experience. The more drives you add to the array, the faster the transfer speeds. A single SSD will be faster and more reliable, although way more expensive for considerably less space. SSD's in RAID would almost certainly be a waste of money given the cost/size ratio, and your CPU would be the bottleneck anyway.

If it had been released in 1996 it would have been ahead of its time, but I'm afraid these systems are just standard HTPC systems, albeit higher-end ones, and quite nice looking too. They're certainly nicer looking than most HTPC's I've seen.

As far as RAID and SSD's go, your CPU will be the bottleneck. The (approx) 40% speed improvement is on read/write operations to the hard drives. Loading applications will be faster, transferring files will be faster, and you will have the capability to capture uncompressed HD video without dropping frames. If you perform a lot of large file transfers from drive to drive or system to system, then you will really like the benefits of RAID. However, if you have a script processing at 10fps then it will still process at 10fps because that's as fast as your CPU can do it.

If you're happy with the performance that the Q6700 brings then that's really what you should get. Motherboard upgrades are not possible in these VGX-XL systems due to the custom form-factor they use, which is a shame because if you could change the motherboard then you could increase performance dramatically for relatively little cost. I'm not convinced a faster GPU would make much of a difference, but of course if you play the occasional 3D game, and/or want to just tweak your system to the max then certainly there is no negative impact, provided your case cooling is adequate. ;)

An observation about overclocking, its interesting how it was once a risky, warranty-voiding endeavour for the cash-strapped and MHz-hungry and these days its used as a marketing gimmick and can actually cost more to implement effectively than just buying a faster CPU or GPU in the first place!

Nice specs!

The only thing to take into consideration is cooling. Two hard drives will add to the internal temperature, especially if they're crammed in next to each other. You choice of graphics card will be crucial too. You don't want something too excessive in there because it will get very hot. I'm guessing you're dealing with low-profile cards, which means you should find a nice compromise as excessive power doesn't really go hand-in-hand with smaller cards.

One more note: any large PCI cards may obstruct the GPU cooler, which is not desirable if it can be avoided; I've seen a GPU cooling fan melted off its bearing due to this, it was dangling onto the sound card that had been put directly underneath it!

RAM with a discreet heat spreader would also be a good choice.

The ESI Juli@ is an interesting card! Its nice that you can swap between balanced and unbalanced I/O by physically rotating half of the card, and the DirectWire feature is incredibly useful. It seems a solid choice for analogue capture.

_,,,^..^,,,_ said:

I'm still looking further info of the comb filter of the Osprey Viewcast PCI models, but without success.

All of the photos I've seen of their cards show a Conexant Fusion 878A chip. The data sheet from 1999 shows that this chip uses a notch filter.

_,,,^..^,,,_ said:

The XL systems was thought as HTPC, and so I think there will be no problems about HDDs heat - infact, in some models there were two, one on top of another, and I heard about no issues about HDDs heat problems, and those models are 6/7 years old... plus, newest HDDs should produce less heat than older, in particular 5900rpm models.

I was talking bigger picture; I also doubt you that would have heat problems with hard drives, but you will have an extra drive in there adding to the overall heat inside the case and taking up a bit of extra space that the air will have to spread itself out it in.

The thing that seems to affect HDD's the most is people dropping them! ;)

Yes, GPU should be low profile; in particular, the AMD based HD 5450, 6570, 6670 and 7750 are the ones tested by many XL users, and all works very well; as the PSU is only 300W, their power consumption is well under their specs, around 50/60W. Still, don't know a lot about Nvidia GT640; it's a new card for "us" XL owners, and should be tested further, but I think it will be OK, too.

PSU's usually produce less power as the capacitors age, but you'll be just fine if you leave a little bit of headroom within your 300W limit, which is a good thing to do even with a new PSU.

RAM: a heat spreader is welcome, but as the max speed is "only" 667MHz for 8GB, and 800MHz for 4GB, I don't think it will be "crucial".

Ah, you've misquoted me here. I said "crucial" in reference to your choice of graphics card. I simply said that a heat spreader is a good idea. Of course, memory at 'only' 667MHz/800MHz still gets hot, the availability of memory now clocked at 1333MHz+ doesn't mean that the old top-spec memory is going to run any cooler than it did 5 years ago.

Actually, all that said, your memory could be 'Crucial' if you wanted it to be... ;)

You might also want to try some quality thermal compound for the CPU to help heat transfer to lower the CPU temperature a few degrees; Arctic Silver 5 is pretty good for this and does work better than the standard thermal compound although the results of 'how much better' can vary, and it is a relatively inexpensive item (or so you will think until you see how small the syringe is, but there is enough for several CPU's).

I've had to repair too many systems in small form-factor cases (and laptops) that have suffered from component failure due to heat, and would rather it not happen to you, Andrea. HTPC cases are generally not high performance. A tool such as SpeedFan will help you monitor temperatures once you have performed your upgrades.

I'm sure you will have little or no trouble, but I figured I'd just give you some food for thought. It would be a shame to have any of your work disrupted by system problems; I'm really looking forward to watching your work on The Thing (when I eventually get around to getting it), and I'm hoping you'll get some more Star Wars-related work done soon.