Re: Question about video-signal adapters (HDMI-to-DVI, etc.)

[Guest guest]

> Is having to use an adapter

> (such as HDMI-to-DVI) signifcantly worse, emf-wise, than a direct

> connection between the computer and monitor?

I tnink an HDMI-to-DVI connector is harmless... they are both the

same signal, except HDMI includes audio. Otherwise, it's just a

different connector, but the same signal.

The real issue I think is whether you tolerate a digital (HDMI/DVI)

signal better than an analog (VGA) signal.

And VGA may look just as good as HDMI if you've got a good quality

monitor and are not using too high of a resolution. I can't really

tell the difference, so I use VGA because it's more tolerable.

(although we have someone else here who uses fiber optic DVI and

says that is better for them than VGA)

Marc

[Guest guest]

>

>

> I tnink an HDMI-to-DVI connector is harmless... they are both the

> same signal, except HDMI includes audio. Otherwise, it's just a

> different connector, but the same signal.

>

> The real issue I think is whether you tolerate a digital (HDMI/DVI)

> signal better than an analog (VGA) signal.

>

> And VGA may look just as good as HDMI if you've got a good quality

> monitor and are not using too high of a resolution. I can't really

> tell the difference, so I use VGA because it's more tolerable.

> (although we have someone else here who uses fiber optic DVI and

> says that is better for them than VGA)

>

> Marc

>

Thanks for the response. The monitor I'm looking at right now is only 18.5 " ,

with a 1360x768 native resolution (I figure that this relatively low-resolution

might be overall more tolerable, and easier on my eyes from a text-reading

standpoint). So I might be well within the territory where there is no

discernable difference between VGA and DVI/HDMI?

(The monitor brand/model, btw is a Samsung Syncmaster E1920X. The Samsung

Syncmaster line is pretty reputable, I think?)

The issue is that the computer I'm considering doesn't have a VGA connection -

only a HDMI and mini display port - so if I decide to go the VGA route I would

need an adapter. Will having to use an adapter to get VGA output signifcantly

degrade the signal? Will an adapter that has to change a digital signal to an

analog signal emit bothersome radiation?

There seems to be a lot of varying opinion as to whether a DVI/HDMI connection

leads to a noticably crisper image over VGA. There are people (like you) who

notices no difference in image quality, then there are those who are adamant

that there is indeed a noticable difference.

There has been some in-store evidence that a VGA connection could be easier for

me to tolerate and has less emf. But if the emf benefits of a VGA connection

would be negated by having to use an adapter to change the digital signal to VGA

signal, would using a VGA connection even be worth it?

~Svetaswan

[Guest guest]

> The issue is that the computer I'm considering doesn't have a VGA

> connection - only a HDMI and mini display port

Ahhh, well if you monitor doesn't accept VGA, then there's nothing

you can do (I don't think). If it were me, I'd try to get a monitor

that had both analog and digital inputs, so I could experiment.

> There seems to be a lot of varying opinion as to whether a DVI/HDMI

> connection leads to a noticably crisper image over VGA. There are people

> (like you) who notices no difference in image quality, then there are

> those who are adamant that there is indeed a noticable difference.

It depends on the monitor. I've used one monitor where there was a huge

difference between HDMI/VGA, and another monitor where you couldn't tell

the difference. This with the same computer.

Marc

[Guest guest]

>

>

> Ahhh, well if you monitor doesn't accept VGA, then there's nothing

> you can do (I don't think). If it were me, I'd try to get a monitor

> that had both analog and digital inputs, so I could experiment.

>

>

> Marc

>

Oh - the monitor accepts VGA...I wasn't trying to say that it didn't. It's the

*computer* that's the " problem " - it doesn't have a VGA port. It only has a

HDMI port and a mini-display-port - and I'm wondering if having to get an

adapter to convert a digital signal to VGA output would negate the emf-benefits

of using a VGA connection.

And like I said, I'm also wondering if the digital-to-VGA conversion process

would degrade the VGA signal to any significant extent.

But yeah, the monitor itself has both a VGA port and a DVI-D port.

~Svetaswan

[Guest guest]

> It's the *computer* that's the " problem " - it doesn't have a VGA port.

> It only has a HDMI port and a mini-display-port - and I'm wondering if

> having to get an adapter to convert a digital signal to VGA output would

> negate the emf-benefits of using a VGA connection.

Looking at the mini-display-port to VGA adaptor at the Apple Store, that

doesn't look like it would cause any trouble. There is no external

power source, which indicates to me that perhaps that your computer

can output either digital or analog to the mini-display-port, which

means that the adaptor is not *converting* anything, but just

*adapting* from one type of connector to another. So there would be

no degradation either, assuming you use a high-quality VGA cable

(which costs virtually nothing these days)

Marc

[Guest guest]

> Thanks for the response. The monitor I'm looking at right now is only

> 18.5 " , with a 1360x768 native resolution (I figure that this relatively

> low-resolution might be overall more tolerable, and easier on my eyes

> from a text-reading standpoint). So I might be well within the territory

> where there is no discernable difference between VGA and DVI/HDMI?

Yes, if the monitor has a good quality VGA conversion hardware, then

the VGA and HDMI signal should look the same. If it doesn't have good

VGA conversion hardware, then the HDMI signal may look better.

I'm using a 26 " Sony HDTV (1366 x 768 pixels), and I can't tell the

difference between VGA and DVI, picture-quality-wise. ES-wise, the

VGA option is easier to tolerate.

Marc

[Guest guest]

You getting a MacBook?

My brother just got one (MacBook Pro 15 " i7). I'm on it right now,

and I can tell you it's an electromagnetic nightmare - Bad chest pains,

tinnitus and ear ache.

Yesterday I went to Best Buy to test other laptops. They're all the

same. 100+ milli gauss just above the keyboard with any of the

new i3, i5 or i7 intel mobile chipsets.

I'm sticking with my old HP " live strong " laptop and other HP with

an Ultra Low Voltage processor.

Eli

>

> I might be a situation where, to use the computer/monitor combo that I think

might be relatively o.k. for me (overall) - may require using a HDMI-to-DVI

adapter (plus a DVI cable) to connect my computer to the monitor. Does anyone

know whether these types of video-signal adapters significantly contribute to

emf radiation? Is having to use an adapter (such as HDMI-to-DVI) signifcantly

worse, emf-wise, than a direct connection between the computer and monitor?

Would I be better off trying to use a monitor with a HDMI-port and forgoing the

adapter altogether?

>

> Would a HDMI-to-VGA (or mini display port to VGA) adapter be better? (The

concern about this is that VGA doesn't give as high-quality a picture as HDMI or

DVI.)

>

> I've also been strongly considering using a DVI or HDMI fiber optic cable to

connect the monitor to the computer (this may be contingent on finding a

fiber-optic cable that isn't insanely lengthy). Does one lose the beneficial

effect of a fiber-optic cable if it has to be plugged into an adapter, instead

of the computer itself?

>

> ~Svetaswan

>

[Guest guest]

>

>

> Looking at the mini-display-port to VGA adaptor at the Apple Store, that

> doesn't look like it would cause any trouble. There is no external

> power source, which indicates to me that perhaps that your computer

> can output either digital or analog to the mini-display-port, which

> means that the adaptor is not *converting* anything, but just

> *adapting* from one type of connector to another. So there would be

> no degradation either, assuming you use a high-quality VGA cable

> (which costs virtually nothing these days)

>

> Marc

>

Thanks Marc!

Hopefully, if I end up getting the Mac Mini, that the mini-display-port-to-VGA

connection works out.

From reading the Wikipedia page on video cards, it's a wonder how VGA is more

tolerable than DVI - the info on Wikipedia indicates the exact opposite. First

of all, it says that the few remaining " legacy LCDs " that use VGA input

reconvert the analog signal back to digital before displaying it - so with VGA,

the signal undergoes a digital-to-analog-to-digital conversion journey that

degrades the signal. Then it goes on to say that VGA connections have the

problem of " electrical noise " - while DVI connections avoid electrical noise.

Perhaps Wikipedia is off-base on this one?

http://en.wikipedia.org/wiki/Video_card#RAMDAC (the above claims are under the

" RAMDAC " section, and the subsequent " Outputs " section)

~Svetaswan

[Guest guest]

> From reading the Wikipedia page on video cards, it's a wonder how VGA is

> more tolerable than DVI - the info on Wikipedia indicates the exact

> opposite.

Well, I suspect it varies depending on the person, the video card,

the monitor, and the cables connecting the two. I personally find

analog signals traveling over a wire more tolerable than digital

signals. It doesn't seem to matter about the conversions that take

place within the monitor (no matter what signal you feed a monitor,

some processing takes place within the monitor).

On an unrelated note, I got my first battery-free watch in the mail

today, and my initial impression is that it's less tolerable than

my battery watch! (it also has a lot more metal in it, and glows

in the dark much brighter, so these factors may be more important

than whether it has a battery)

Marc

[Guest guest]

>

>

>

> You getting a MacBook?

>

> My brother just got one (MacBook Pro 15 " i7). I'm on it right now,

> and I can tell you it's an electromagnetic nightmare - Bad chest pains,

> tinnitus and ear ache.

>

> Yesterday I went to Best Buy to test other laptops. They're all the

> same. 100+ milli gauss just above the keyboard with any of the

> new i3, i5 or i7 intel mobile chipsets.

>

> I'm sticking with my old HP " live strong " laptop and other HP with

> an Ultra Low Voltage processor.

>

> Eli

>

Hi Eli

Yeah, Apple may have reached the point where they are packing too much " stuff "

into a too-small chassis, when it comes to their Macbooks. I suppose even the

highly-sophisticated throttling/power-management techniques that Macbooks use

isn't enough to " save " some from the emfs (including myself, I guess).

But no - I'm not getting a Macbook (at least not today I'm not ). I could

change my mind at any time, but right now I'm planning on a Mac Mini. I know I

slammed the Mac Mini when I saw the new, thinner bodystyle (which includes the

built-in power supply) - but weighing the alternatives forced me to reconsider.

The Dell Zino apparently has major reliability issues, from scanning some of the

user feedback. And I'm not comfortable with placing a full-sized desktop in my

bedroom - with all of the " heat " it could generate. And I much prefer a company

that offers solid technical support - so that ruled out nettops like the Asrock

Nettop and the Acer Aspire Revo. And for various reasons, I'm not too

comfortable with purchasing a laptop, especially if my e.s. dictates that I use

it as a virtual desktop. I haven't been able to " test " many laptops, anyway.

Yes, the Mac Mini has that built-in switching power supply - but I've been

trying to convince myself that it would be o.k.. Maybe the aluminum unibody of

the Mac Mini shields most of the emf. Maybe Apple designed a kick-a$$

power-supply that minimizes noise. If they are packing the power-supply into

that small chassis - surely they must have accounted for " electromagnetic

interference " ? After all, you can't have the emfs from the power-supply

interfering with the other components.

Btw, I just read that the Core i7 chip has a TDP of 45W! My 2001 Gateway

full-sized desktop had a processor with a TDP of 53W.

~Svetaswan

[Guest guest]

The max TDP of the i7 is the same as the i5, 35 W.

At least that's what Intel says. What they should really

rate is the average TDP.

Did you take a look at the Samsung XL2270 monitor? It has an external

power supply. I haven't measured it, but it may be worth a look.

As for netbooks, the HP mini 210 had the lowest magnetic field of them

all. It was 3-7 milli gauss, but pulsed up to 15 mg every 5 seconds. All the

other netbooks were at 35-50 milli gauss just above the keyboard.

Gotta get off this EMF monster now. I thought maybe the aluminum uni-body

would help the Mac Pro but I was wrong - maybe it helps with some of the

higher frequencies, but the devastating lower frequencies go right through.

Eli

> >

> >

> >

> > You getting a MacBook?

> >

> > My brother just got one (MacBook Pro 15 " i7). I'm on it right now,

> > and I can tell you it's an electromagnetic nightmare - Bad chest pains,

> > tinnitus and ear ache.

> >

> > Yesterday I went to Best Buy to test other laptops. They're all the

> > same. 100+ milli gauss just above the keyboard with any of the

> > new i3, i5 or i7 intel mobile chipsets.

> >

> > I'm sticking with my old HP " live strong " laptop and other HP with

> > an Ultra Low Voltage processor.

> >

> > Eli

> >

>

>

> Hi Eli

>

> Yeah, Apple may have reached the point where they are packing too much " stuff "

into a too-small chassis, when it comes to their Macbooks. I suppose even the

highly-sophisticated throttling/power-management techniques that Macbooks use

isn't enough to " save " some from the emfs (including myself, I guess).

>

> But no - I'm not getting a Macbook (at least not today I'm not ). I could

change my mind at any time, but right now I'm planning on a Mac Mini. I know I

slammed the Mac Mini when I saw the new, thinner bodystyle (which includes the

built-in power supply) - but weighing the alternatives forced me to reconsider.

The Dell Zino apparently has major reliability issues, from scanning some of the

user feedback. And I'm not comfortable with placing a full-sized desktop in my

bedroom - with all of the " heat " it could generate. And I much prefer a company

that offers solid technical support - so that ruled out nettops like the Asrock

Nettop and the Acer Aspire Revo. And for various reasons, I'm not too

comfortable with purchasing a laptop, especially if my e.s. dictates that I use

it as a virtual desktop. I haven't been able to " test " many laptops, anyway.

>

> Yes, the Mac Mini has that built-in switching power supply - but I've been

trying to convince myself that it would be o.k.. Maybe the aluminum unibody of

the Mac Mini shields most of the emf. Maybe Apple designed a kick-a$$

power-supply that minimizes noise. If they are packing the power-supply into

that small chassis - surely they must have accounted for " electromagnetic

interference " ? After all, you can't have the emfs from the power-supply

interfering with the other components.

>

> Btw, I just read that the Core i7 chip has a TDP of 45W! My 2001 Gateway

full-sized desktop had a processor with a TDP of 53W.

>

> ~Svetaswan

>

[Guest guest]

>

> > Well, I suspect it varies depending on the person, the video card,

> the monitor, and the cables connecting the two. I personally find

> analog signals traveling over a wire more tolerable than digital

> signals. It doesn't seem to matter about the conversions that take

> place within the monitor (no matter what signal you feed a monitor,

> some processing takes place within the monitor).

>

> On an unrelated note, I got my first battery-free watch in the mail

> today, and my initial impression is that it's less tolerable than

> my battery watch! (it also has a lot more metal in it, and glows

> in the dark much brighter, so these factors may be more important

> than whether it has a battery)

>

> Marc

>

So the relative intolerability to a DVI or HDMI-connected screen is solely about

the emfs radiating from the connecting wire - and not the increased emfs that

may be radiating from the screen due to the digital input signals?

I've said that I've had some in-store " evidence " that I may tolerate VGA screens

better...well, I looked at the exact same LCD monitor in two different stores,

and I noticed that the screen at one location was pretty " quiet " using the

AM-radio test, while this same screen at a different store had significantly

more RF noise. (I made sure that each screen was at full brightness before I

" tested " them.) Since the screen with the RF noise displayed a crisper image

than the " quiet " screen, I kinda assumed that it was using the HDMI connection,

while the quieter screen was using a VGA connection.

And when I was looking at the Samsung Syncmaster that I already mentioned in

this thread - I noticed that there was something about standing in front of the

screen that seemed " more stressful " than standing in front of a different

Samsung Syncmaster (same sized-screen) with only a VGA connection. Although the

text on both screens was blurry (because they were displaying at 1060x768 -

slightly lower than their native resolution), there was something about standing

in front of the screen with just the sole VGA connection that seemed easier on

the eyes. I don't think it was screen brightness - if anything, the VGA-only

Samsung seemed brighter than the dual-input Samsung. I wonder if it was a

matter of VGA vs. DVI connection. (I didn't do the AM-radio test on these two

monitors because the " atmosphere " in the store heightened my

self-consciousness.)

Sorry to hear about your watch - it must be a solar-powered watch?

~Svetaswan

[Guest guest]

>

> I'm using a 26 " Sony HDTV (1366 x 768 pixels), and I can't tell the

> difference between VGA and DVI, picture-quality-wise. ES-wise, the

> VGA option is easier to tolerate.

>

> Marc

>

Part of me would love to do what you have done, and use a LCD TV as my computer

monitor. That way I could ensure large, readable font on even a 22 " screen -

and I could try to sit at a greater distance and still be able to read text.

But there are just too many " unknowns " - I haven't been able to do any " eye

tests " on LCD TVs as computer monitors. I'd like to be able to use the screen

at full-brightness to avoid the emf-generating dimming mechanism - and LCD TVs

might be too bright to use at full-brightness. I think they may make LCD TVs

brighter than monitors in order to get a more " cinematic " effect on t.v. and

movie images, and because it is assumed that people will be sitting at much

greater distances from these TVs than they sit from computer monitors.

Do you use your 26 " LCD TV as a TV, also? Do you have several " inputs " attached

to it - i.e. computer, cable box/DVR, etc.? I'm wondering how having several

objects attached to a LCD TV - such as cable box, DVD-recorder, computer, etc. -

affects everything from a emf standpoint.

Because I'm suddenly wondering if it would be better overall if I bought a large

26 " LCD TV - and attached the Mac Mini to it as well as everything else - my

cable TV, and whatever DVR or DVD-R I choose. Like yourself, I could sit at a

relatively greater distance from this hub. Or would it be better to just

implement the plan I already have in mind - get a 18.5 " " office " monitor to

attach to the Mac Mini, then later (perhaps) get a separate 22 " LCD TV to attach

cable and DVD player? Whatever option I choose, all of this will be sitting on

my dresser in my bedroom.

~Svetaswan

[Guest guest]

> So the relative intolerability to a DVI or HDMI-connected screen is

> solely about the emfs radiating from the connecting wire - and not the

> increased emfs that may be radiating from the screen due to the digital

> input signals?

Well, keep in mind that I am not measuring anything other than my own

symptoms, but yes, it seems a lot like my symptoms are caused by what's

radiating out of the DVI/VGA/HDMI cable.

> Sorry to hear about your watch - it must be a solar-powered watch?

No, spring powered, self-winding " automatic " watch... I haven't given

up on it just yet... but it may indicate that the battery is not the

issue, and rather the amount of metal in the watch is something that

should be minimized.

Marc

[Guest guest]

> I'd like to be able to use the screen at full-brightness to avoid the

> emf-generating dimming mechanism

My experience with LCD monitors and TVs is that dimming the screen

HELPS, not hurts. This seems to be an exception to the rule that

dimmers are bad.

> Do you use your 26 " LCD TV as a TV, also?

No, I use it just as a computer monitor. No other wires are going

into it other than the VGA and power cable.

My TV is a 37 " HDTV, with all sorts of signals feeding it. But

I sit 10 feet away from that.

Marc

[Guest guest]

>

>

>

> The max TDP of the i7 is the same as the i5, 35 W.

> At least that's what Intel says. What they should really

> rate is the average TDP.

>

> Did you take a look at the Samsung XL2270 monitor? It has an external

> power supply. I haven't measured it, but it may be worth a look.

>

> As for netbooks, the HP mini 210 had the lowest magnetic field of them

> all. It was 3-7 milli gauss, but pulsed up to 15 mg every 5 seconds. All the

> other netbooks were at 35-50 milli gauss just above the keyboard.

>

> Gotta get off this EMF monster now. I thought maybe the aluminum uni-body

> would help the Mac Pro but I was wrong - maybe it helps with some of the

> higher frequencies, but the devastating lower frequencies go right through.

>

> Eli

>

Ah - I guess I should have verified the i7 TDP at the Intel website, instead of

taking another website's word for it.

The Samsung XL2270 monitor looks nice - but here come the " buts " . That

native resolution is too high for comfort - Mac OS X doesn't have quite the

text-enlarging options as Windows, so a screen's native resolution takes on

greater importance for me. Besides, the higher resolution may lead to less

tolerability from an emf-standpoint - perhaps because of the heightened signals

that the video card outputs to the monitor (I learned this from an old post of

Marc's ). And I don't know how I would tolerate the brightness - one thing

I've learned is that, although all the monitors list their brightness at 250

nits or 300 nits - manufacturers lie about these specs - and their *real*

brightness levels can vary pretty widely. LEDs tend to run brighter than CCFLs,

I think. And dimming the screen brings about the same emf-generating mechanism

as CCFL screens, right?

Do you have this monitor? I doubt I've seen this display in real-life, just

wondering if you have.

Bummer about the Macs and their low-frequency magnetic fields. I guess this is

one of the reasons why Apple's products aren't TCO-certified. I don't think

I've been as concerned with the low-frequency magnetic fields because these

fields don't seem to give me overt symptoms. At least I don't think they do? I

mean, I can lay close to the large 27 " CRT-TV in our den and not feel much

discomfort. (Although that same TV in my much-smaller, poorly-circulated

bedroom might be a different story.)

I realize that I should perhaps be more concerned about these low-frequency

fields anyway - from a health standpoint. Aren't low-frequency magnetic fields

easily mitigated by distance?

~Svetaswan

[Guest guest]

>

> My experience with LCD monitors and TVs is that dimming the screen

> HELPS, not hurts. This seems to be an exception to the rule that

> dimmers are bad.

>

> Marc

>

Well, my own experience in dimming a LCD monitor has been a very mixed bag.

When I dim the screen on this laptop, my eyes (and perhaps my skin) thank me -

but at the same time, the increased RF (that I can actually " measure " via an AM

radio) is bothersome, I think. And dimming the screen seems to cause increased

RF to radiate not only from the screen, but also from the computer keyboard

area, from the cord leading from the power supply, and from the power-supply

itself. Some of these RF frequencies seem to have a broad range. There are a

few frequencies that the radio seems to detect many feet away - far greater

distances than you would think a mere laptop would be able to reach.

I sometimes notice a certain relief when I turn the screen back to full

brightness. But sooner or later - this relief is tarnished by my sensitivity to

the bright screen.

When I used this laptop with the dimmed monitor in my bedroom, I even pick up RF

noise on my bed! (I don't use the laptop on my bed, but the laptop's sreen is

about 3 feet from the side of the bed.) I assume that this noise is being

emanated from the metal springs inside my mattress. Just recently, I turned the

screen back up to full brightness, then ran the AM radio test on my bed again.

The RF noise - at least the portion of it detected by AM radio - seemed to

disappear.

But it's " weird " that a dimmed laptop monitor placed about 3 feet from my bed

would cause increased RF noise emanating from my bed. And I'm not just talking

about the side of the bed closest to the screen - I'm talking about all over my

bed (at least the surface).

This overall experience from dimming the screen causes me to want to avoid as

much as possible having to do it.

~Svetaswan