Intel I7 1.99GHz not fast enough for 2mhz+ bandwidth on HDSDR /SDRPlay?

[Beamin]

I have a brand new i7 1.99ghz 8 mb ram SSD 256gb, with most of the windows bloat ware taken off.

On my old i3 laptop I could handle up to 10 MHz bandwidth on my SDR before the audio got too choppy, ten was the max. I tried three mhz on this one and it got choppy, tried 20 and it was unusable.

This doesn't make sense to me. Am I doing some thing wrong? It is a lap top with cord plugged set to max performance settings. I was expecting a 3 year newer computer run flawlessly.

This might be the only reason to buy a faster machine I don't run games or anything too heavy on the CPU.

[Beamin]

So I just found this screen by chance seconds after making that last post. As far as me hearing ghosts in my last thread and that DC spike I would fix that in this screen by changing IFMODE from zeroIF to Low IF? The bandwidth in this screen is different from the bandwidth on the main screen: The main screen bandwidth means you will see on the water fall 100 to 120Mhz on your spectrum if you are set to 20 MHz bandwidth (normal default is 2 also what has least system resources) Conversely on this screen if bandwidth was X for the last example this would be like Z coordinate or depth as I imagine it. This means it measures 2mhz of actual samples at each frequency point?

Why do my ADC control get zeroed out when I go to "low IF" mode? Why does this screen only have the IFBandwidth setting from 0.2mhz to 1.6Mhz, what happened to 20 MHz?

I thought I had figured it out now I'm none the wiser.

[Beamin]

What computer? Post a full part number (i.e. Lenovo ThinkPad X1 Gen 6 20KH-002HUS).
I'm not aware of any 2GHz base frequency i7 chips released in this year and last year.

\\

HPPavillion x360 win 10 home 1709 core i7 8550 @ 1.88  1.99ghz 8 g ram

[ogden]

that DC spike I would fix that in this screen by changing IFMODE from zeroIF to Low IF?

DC spike does not do any harm, just tune your receiver such a way it is outside signal of interest. I don't know much about SDRplay and their receivers, but usually you would lose half of receive bandwidth by changing receive mode from zero IF to low IF. I would not bother.

[TheBay]

That CPU is more than powerful enough to run any of the SDRPlay's especially@10MHz bandwidth.
I've bought several SDRPlay devices and have a RSP1 at my local Ham Radio club running fine on an old Core2Duo.

I currently use the RSP1A at home.

When you say "Choppy" is that the audio or the whole computer, could it be a latency issue?
Have you tried SDRUno, SDR Console V3 or SDR#? Is the problem just with HDSDR?

[Beamin]

What computer? Post a full part number (i.e. Lenovo ThinkPad X1 Gen 6 20KH-002HUS).
I'm not aware of any 2GHz base frequency i7 chips released in this year and last year.

\\

HPPavillion x360 win 10 home 1709 core i7 8550 @ 1.88  1.99ghz 8 g ram

It's a quad core chip with the same power envelope of a dual core chip. As a result, when other cores are running (i.e. Windows Update), the core which your app runs on has less power allocated to it, hence it throttles.

You can use Intel XTU to override the TDP wall. It will still hit temperature wall if it gets too hot, but if your thermal is good, you can extract some considerable more performance from it.

Also, try to undervolt your chip. It drastically (20%+) decreases CPU power at a given speed, hence increasing performance at a give power/thermal limit.

This a lap top so while I don't use it on battery mode often I want it still to have decent life my only intensive program is the SDRUno.

When I say choppy I'm talking about the audio which I listen to SW mainly trying to get dx. As I turn up the band width the audio pays for maybe 0.8 seconds of each second when the bandwidth is way up I hear about 02.sec of each second like a 1 hz pcm signal at 20% is how it sounds. Totally in listenable and annoying. The DC spike issue is not something I can live with because it looks like you are finding signals every time you set the frequency even though you are not. To tune above then retune would take forever so not a solution.


As far as using the IntelXTU are talking overclocking and all that in depth messing with the computers settings? If I need to do that and an i7 is not powerful enough to run SDRUno I think there are other problems. I can't see why you would need that much chip speed to run a slight increase in bandwidth when I have had this working on a netbook and i3 from 3 years ago. Yes the net book would only run at 2mhz but now that I think of it I don't remember having any problem with the i3 or Celeron. If I was trying to record big chunks of spectrum to decode digital signals live on the air waves that would be a different situation, but even then I have never heard people mention they have some crazy over clocked computer to do it. I need something practical. Messing with the clock speed voltages/battery life over heating/ shorter processor life, and really in depth technical stuff for a simple problem doesn't seem right. This software will even run a pi3b.

[TheBay]

What computer? Post a full part number (i.e. Lenovo ThinkPad X1 Gen 6 20KH-002HUS).
I'm not aware of any 2GHz base frequency i7 chips released in this year and last year.

\\

HPPavillion x360 win 10 home 1709 core i7 8550 @ 1.88  1.99ghz 8 g ram

It's a quad core chip with the same power envelope of a dual core chip. As a result, when other cores are running (i.e. Windows Update), the core which your app runs on has less power allocated to it, hence it throttles.

You can use Intel XTU to override the TDP wall. It will still hit temperature wall if it gets too hot, but if your thermal is good, you can extract some considerable more performance from it.

Also, try to undervolt your chip. It drastically (20%+) decreases CPU power at a given speed, hence increasing performance at a give power/thermal limit.

This a lap top so while I don't use it on battery mode often I want it still to have decent life my only intensive program is the SDRUno.

When I say choppy I'm talking about the audio which I listen to SW mainly trying to get dx. As I turn up the band width the audio pays for maybe 0.8 seconds of each second when the bandwidth is way up I hear about 02.sec of each second like a 1 hz pcm signal at 20% is how it sounds. Totally in listenable and annoying. The DC spike issue is not something I can live with because it looks like you are finding signals every time you set the frequency even though you are not. To tune above then retune would take forever so not a solution.


As far as using the IntelXTU are talking overclocking and all that in depth messing with the computers settings? If I need to do that and an i7 is not powerful enough to run SDRUno I think there are other problems. I can't see why you would need that much chip speed to run a slight increase in bandwidth when I have had this working on a netbook and i3 from 3 years ago. Yes the net book would only run at 2mhz but now that I think of it I don't remember having any problem with the i3 or Celeron. If I was trying to record big chunks of spectrum to decode digital signals live on the air waves that would be a different situation, but even then I have never heard people mention they have some crazy over clocked computer to do it. I need something practical. Messing with the clock speed voltages/battery life over heating/ shorter processor life, and really in depth technical stuff for a simple problem doesn't seem right. This software will even run a pi3b.

How does it perform when it's plugged in to mains, are your power settings too conservative?
Is it the same on all SDR applications, have you checked your audio latency or system latency?

Nearly all radios have a DC offset, be it heterodyne, sdr, up or down conversion. You need to move the LO outside of the frequency range you wish to view.
That's not a fault or an issue, its how they work.

[Beamin]

How does it perform when it's plugged in to mains, are your power settings too conservative?
Is it the same on all SDR applications, have you checked your audio latency or system latency?

Nearly all radios have a DC offset, be it heterodyne, sdr, up or down conversion. You need to move the LO outside of the frequency range you wish to view.
That's not a fault or an issue, its how they work.

I'm aware of the DC offset just want sure how to change it. The choppiness isn't normal SDR, offset makes a totally different problem, like you can still listen  to DXSW voice with the offset problem, but its unuseable with the choppiness. I have had a few and been using these for a few years on many different machines. The lap top was plugged in and set to performance. This is a new lap top and I just found MacAfee lurking in the background that slows your system more then a virus. Since I haven't got all the bloatware off maybe that's the problem. How do you check audio latency or system latency is there a tool in windows system/settings, just the CPU monitor? Never heard of audio latency. I know the SDR can use a lot of cpu power sometimes but don't know how to check it there used to be a graph in one of the sdr applications but they don't have that anymore.

[medical-nerd]

Hiya

Slightly off topic I know but I've just picked up a server from the usual auction site that I'm going to strip down and make a rig just for SDR use :

SuperMicro X8DTG-DF motherboard
2 x Xeon Quad core E5620 2.4GHz giving 16 threads total
48Gig ram

I plan to use the motherboard and power supply, add CPU coolers, a graphics card and USB 4x card +/- sound card.
My only concern is that I may have to mount additional fans above the memory slots - but still this will be quieter than the original server.

I know that its an old system but the whole setup including new CPU coolers is only costing about £150 including a new 240Gig SSD and is for gnu-radio on Gentoo Linux. Hopefully enough for my 4 x V3 RTL-SDR, 2 x ThumbNet N3 and RSP1a.

Cheers

[David Hess]

You might need to disable some of the CPU's power management features.  They could be interfering with real time operation.

[Beamin]

You might need to disable some of the CPU's power management features.  They could be interfering with real time operation.

That computer just sucked. The fan was always running full blast when ever I have more then 3 youtube videos up at a time. It had weird glitches and would often freeze IE and would lose connection to the wifi a lot.
For an i7 it seemed like the processor was running full speed to handle small programs and the battery suffered from it. Brand new too. Also the keys were getting sticky. So that HP one goes back to the store. Heavy not fun to balance on your legs.

I just got a surface 2 with the detachable screen that is an i5  7300 but runs at 2.6 2.7ghz so faster then the i7 kind of? So far I haven't heard the fan turn on once keyboard feels really good and the whole build quality feels solid and light. Was 1200 normally 1400. I use the lap top 8 hours a day everyday for about 3 or 4 years so I want it to be a good one.

Also the screen on this one is so much better then those last three. The black is black and the resolution is really crisp and the colors are bold. Does 2160p in amazing color. The screen detaches with an electronic switch that's a key on the key board no mechanical button. Its really thin but they have a curve in the top making it as thin as a normal lap top but if the thing folded flat it would be incredibly thin. No bug glitches so far and not much bloat ware to remove so far.
Two batteries is cool; one in the key board and one for the tablet, so you get double the battery.
Haven't tried SDR on it yet.

[RoGeorge]

I would look for these 2 causes:
- Core parking in Windows <- Google for 'aggresive core parking fix windows i7', and apply the patch (a registry key)
- USB bandwith / USB drivers problems <- contact the SDR device manufacturer for the latest drivers