Sager Design - Latency?

Am looking for a notebook to do both gaming and real-time audio recording.

I can spec out a machine on paper, but one of my biggest concerns is latency (such as DPC).

Are Sagers (Clevo) designed and built to achieve low latencies?

Thanks!

 

Got a feeling no one knows what you are talking about.

Latency is your concern? What is DPC?

Built to achieve low latency?

Normally, latency is a term used to apply to the delay between when a process is initiated and when the response occurs.

Most of the time, people use this term along with "lag" when playing online games.

As such, latency is a product of your network (or more specificlally, your location on the internet in relation to the game server) or the quality of the connection.

This has nothing to do with a laptop/pc's design or build quality.

However, latency can also be applied to wait states in a computer--for example, if the CPU and Memory operate asynchronously or synchronously, or the speed of the memory....

Seriously, though, this latter kind of latency is imperceptable--you might pick it up with a benchmark utility, but people worry too much about such things.

 

Latency is, by definition, a time delay. Let me just call it time delay.

In playing online games, there is the time delay associated with your PC (desk or laptop) wrt all the hardware and software running and then there is the time delay associated with the network connectivity starting from your port outwards thru router, isp, backbone, etc. I am concerned with the first.

For gaming, time delay, whether it be PC or network, of 40 ms or less is difficult to detect. For audio recording however, the threshold is 10 ms. Have dialed the later in with a Lexicon rack effects processor, and it is real.

As far as design, there are some things you can do (badly) that affect hardware peformance. Heat is a biggie; inadequate ventiallation for video gpu. Incompatibility between hardware chipsets that don't cause crashes, but peformance issues on the scale I'm concerned. Have experienced both on PCs and was able to mod config/swap parts to resolve. Laptop is a different matter.

One I've come across recently is time delay associated with Deferred Procedure Call (DPC). Confess I don't fully understand the details, but as per wiki "When working with streaming audio or video that uses interrupts, DPCs are used to process the audio in each buffer as they stream in. If another DPC (from a poorly-written driver) takes too long and another interrupt generates a new buffer of data, before the first one can be processed, a drop-out results".

There is a tool to check http://www.thesycon.de/deu/latency_check.shtml

Have downloaded and run this app on some laptops already. My wife's Samsung wasn't too bad, but not optimal. Someone here posted a snapshot of their Sager 81XX series,and it was sweet. Tried it on some Sony Vaio's at a store and, if it is to be believed, they were crashin' and burnin'.

May be naive, but given that gaming -is- one of the most stressing uses of a PC/Laptop, was hoping that a gaming-specialty house such as Sager includes in their specs to Clevo low latency/lag/time delay.

Granted, there is nothing Sager can do to avoid an -updated- driver put out by an OEM becoming a DPC issue.

 

The question is are you going to be using the firewire port for your audio work? The Sagers have been using in recent laptop versions the JMicron controller chip, which is not as good as the TI. Otherwise if your using USB audio devices you should be ok.

 

I've been using the DPCLat Checker for latency related tests on hundreds of notebooks and can try to help answering the question.
First, what model/configuration are you interested in?

Normally, you can expect the latency in the 100-300μs except for occasional spikes associated with video cards up-down-clocking (PowerPlay/PowerMizer), wireless, etc. Sager's are no different from the majority of laptops in this aspect.

Attached is a screenie from a X7200(NP7280) with 480M SLI

 

Thanks, that's good to know! I do have a Presonus that is firewire, but was intending to switch to a smaller interface using USB.

 

Great, really appreciate it!

The Vaio I haven't been able to check, hasn't been in stock, is the VAIO VPCF13YFX/B. Video card is a midling 425M.

Also looking at Sagers 5160/5170 or 8130/8150. I like the idea of Optimus (51XX) for heat, battery life, but unsure of implementation.

 

I don't have the 5160/5170 by my side but the 8150 has an even better latency than the NP7280 - under 200μs. You could ask people in the owners lounges to run the Checker and post their results.

 

What about the 8170?

 

If you already have the the system, run this tool. According to Notebookcheck, it's ok (scroll down to the "Verdict: Performance")

 

I have the NP8170. Not sure what all this means, but I ran some youtube stuff and some audio files I had and it spiked to about 1750μs otherwise in general was below 1000μs. Anything in particular (and easy) that you want me to run to see? I'm clueless with this stuff so just laugh quietly behind my back.

 

^^ That's perfectly fine. Browsing with multiple tabs and lots of flash as well as scrolling large PDF's will result in up-clocking the GPU and produce some spikes. My machine hits up to 5-6k while browsing.