AGP to LCD questions

[josh22205]

Hello all,

I've posted once before on this forum; however, when I did I was mostly looking simply for confirmation that a crazy I idea of mine was POSSIBLE. Now I'm better informed and looking for detailed info... allow me to explain:

I am an EMT, which means that when I'm not on an ambulance running to a call, I'm sitting at my station for 24 hours a shift... yeah it does get a lil dull during our down-time. Further, I have no access to a PC at work and I love console gaming (via emulators) and RPG gaming, as well as DVD movie watching (love "B" martial arts movies on DVD). I am an A+ Tech and fairly computer savvy, having built several and worked on more.

Thus hatched my insanity: a "portable desktop/upgradeable laptop hybrid" -- in short, I am constructing a DIY laptop from off-the-shelf components.
My projected components list includes:
-- MSI K7N2 Delta-2 LSR ATX mobo,
-- Diamond Viper II AGP card,
-- Athlon XP-M 2500+ CPU,
-- 512MB PC3200 DDR
-- 300 Watt (or better) Power Supply Unit
-- PCMCIA Card slot (PCI Bus)
-- 80-100 GB WD HDD (dunno whether SATA or EIDE)
-- DVD Burner (dunno what brand yet)
-- 1.44MB FDD (oldie but a goodie)
-- and a home-made case. All this is by no means new or state-of-the-art... but I'm working with a shoestring budget right now too! Ha! (eBay all the way, Baby!)

My question here is related to the display issue. I know through some research that a proprietary laptop LCD is a no-no cause they're nearly impossible to work with alone, to say nothing of pumping video data through an AGP card to them. Thus I have decided upon a (REAL) thin panel LCD monitor for my display.

My questions are these:

1. Is it possible, in fact, to feed data to an LCD monitor from an AGP card (and in future a PCIe card)?

2. What type would you recommend: XGA, SXGA, WSXGA, WTFXGA? (ok I made the last one up)

3. Is it possible (and safe) to run an LCD monitor off of a regular ATX power supply (provided the PSU is 300 watts or better)?

4. Will I require anything more then some VGA cables and maybe some gender changers (or am I looking at re-inventing the wheel here)?

I know this is asking alot, but what lil I've read of these forums, y'all are knowledgeable and prompt with answers... so I turn to you for advice... Thanks again for any and all help with this "pet project" of mine!

Best regards...

Crystalfontz LCD Blog

Looking for additional LCD resources? Check out our LCD blog for the latest developments in LCD technology.

 

[cosmicvoid]

The video feed should be as simple as a standard VGA type cable (or DVI cable, if you get a video card and LCD that has DVI). What you'd really want is a LCD monitor that has a 12 vdc power requirement, so you can run it off the main PS instead of the monitor's brick supply. I'm not sure how easy it will be to obtain that info (voltage of the brick) for every monitor you are interested in.

Why is it you want a "thin" LCD? Are you attaching it to the side of your case (instead of leaving it free-standing)?

 

[josh22205]

-- quote -- Why is it you want a "thin" LCD? Are you attaching it to the side of your case (instead of leaving it free-standing)?

Yes. I don't want to have more than one piece of equipment to transport. Thank you for replying so quickly.

 

[josh22205]

Does anyone know where to find a stinking L2305 (or equiv.) AC to DC inverter for an LG/Philips 15" LM151X2-C2TH LCD monitor? Or will I even need one if I wire straight to the PC's PSU (yeah, I know I will... just hoping)

 

[DoctorWhosit]

Dont Grab The Thick Red Wire!!!!!

NO NO NO the standard 300W PS from your PC will not support the output amperage required for the Backlight Inverter. Depending on the screen make model and size they can draw anywhere from 4 to 10 amps which would make your PS last for about 10mins. There are VGA to LCD conversion kits for sale on Ebay from about $40 Aus and they claim to have all the parts in the kit & can match & supply the correct cable to connect to the LCD screen socket if you give them the model of screen you are planning to use when you buy the kit.

I have read alot of forums on this subject as I am planning to try and do the same thing with an old Laptop LCD in an Aluminum Briefcase & the one thing that keeps coming up is the issue of power for the Backlight Inverter & it seems the best result is gained by adding an independent power supply for it. The other major issue that nearly every successful converter has posted about is that though the power may only be a measly 12V or so the power out of the inverter has a high amperage and a few people have fried their PC or components, blasted holes in their LCD screens, cooked their power supplies or severely burnt their fingers while building & connecting their kits.

Try the following link to this successful conversion it may help you.

www.pcclub.com/forum/arcmessageview.cfm?catid=28&threadid=2611

It has pictures of the work & detailed steps that he took through the whole conversion

www.stores.ebay.com.au/Eparts138-Store This is the Ebay store I saw the kits available from.

Hope you are successful & if you are please post up how you went & Pictures of the finished product.

As for myself, I think I might just buy a cheap laptop off ebay & put sandwiches in the breifcase.

 

[cosmicvoid]

NO NO NO the standard 300W PS from your PC will not support the output amperage required for the Backlight Inverter. Depending on the screen make model and size they can draw anywhere from 4 to 10 amps which would make your PS last for about 10mins.

Most LCD monitors smaller than 20" draw less than 50W, according to the spec sheets I've seen. A "standard 300W PS from your PC" should handle more than 4A on the 12V output, and larger PC PSs are available.

The other major issue that nearly every successful converter has posted about is that though the power may only be a measly 12V or so the power out of the inverter has a high amperage ....

The inverter for backlighting typically puts out a few hundred volts at a few milliamps, hardly what I'd call "high amperage".

It may be that you actually do know what you're talking about, but I can't tell that by what you've written.

 

[DoctorWhosit]

Shocking absolutely Shocking

Well it is not recommended that you hook the Inverter up to the same power supply as your motherboard is running off for several reasons. A surge back from the inverter could cook the PS, Motherboard or HDDs.

An inverter takes a smaller voltage & turns it into a larger one & though it may only put out a small current as an end result it uses a high currant draw to boost the power up to the higher voltage.

I am not as well versed on the LCD inverters as I would like to be. I was mainly repeating what others have said in their posts about the inverters for their LCDs. I can however tell you that the inverter found in the back of a TV or other CRT screen or monitor can boost up to 1000V & although it may not be a high amperage it certainly leaves the arm (and half my face at the time) feeling pretty numb followed by excruciating pain through the chest, arm & face. I dont like inverters, sure they are useful but when you forget which end of it you are holding it can be a shocking experience. Another mishap I had was while connecting a 240V Light up to a 24V truck battery. I was twisting one set of wires together while my friend thought it would be a great idea to help out by connecting the other end to the battery for me. Not helpful at all.

 

[DoctorWhosit]

Most LCD monitors smaller than 20" draw less than 50W, according to the spec sheets I've seen. A "standard 300W PS from your PC" should handle more than 4A on the 12V output, and larger PC PSs are available.The inverter for backlighting typically puts out a few hundred volts at a few milliamps, hardly what I'd call "high amperage".

It may be that you actually do know what you're talking about, but I can't tell that by what you've written.

Sorry you are correct I mixed my figures around it is only a few milliamps at a high voltage but this can still have a devastating effect if the wires cross a 12V circuit or come in contact with your skin. Amps is what kills but I still dont recommend grabbing a few hundred volts.

 

[cosmicvoid]

Well it is not recommended that you hook the Inverter up to the same power supply as your motherboard is running off for several reasons. A surge back from the inverter could cook the PS, Motherboard or HDDs.

I'd put this in the category of 'extremely unlikely'; it sounds more like FUD to me. I'm not really sure what you mean by "surge back". Did you ever think a surge back from the motherboard or the HDDs could cook the PS? How many times have you heard of that happening?

An inverter takes a smaller voltage & turns it into a larger one & though it may only put out a small current as an end result it uses a high currant draw to boost the power up to the higher voltage.

Yes, true, but we already know that the total draw of the LCD monitor is less than 50W, so the inverter section itself draws less than 4A.

.... at a high voltage but this can still have a devastating effect if the wires cross a 12V circuit or come in contact with your skin.

I agree. You may notice that the high voltage wires have thicker insulation, to prevent this.

I think care is required due to the high voltage, but you are exaggerating the likelyhood of disaster.

 

[DoctorWhosit]

We all bow before thee.

I humbly retire my opinion & my advice to make room for the greater intellect.
Please grace us with thine opinion & thy corrections as thou hast surely seem mine faults & shone a light unto my path.
For it is written, one shall come after me who shall redeem all who have fallen by the wayside.

Would someone please just actually build one of these conversions so we can all see & hear how it went.

By the way Mr Void would you please hold this wire for me

 

[Heffo]

I humbly retire my opinion & my advice to make room for the greater intellect.
Please grace us with thine opinion & thy corrections as thou hast surely seem mine faults & shone a light unto my path.
For it is written, one shall come after me who shall redeem all who have fallen by the wayside.

Would someone please just actually build one of these conversions so we can all see & hear how it went.

By the way Mr Void would you please hold this wire for me

Now, I really don't think that response was necessary. You are entitled to give your advice and "Mr Void" is entitled to give his.

Personally, I have run several CCFL case lighting inverters off the same PSU as my mainboard, HDDs, GPU, etc with no ill effects after several years of almost constant use. Infact, the inverter used on an LCD display would be made with much higher quality standards & components than cheap chinese made CCFL tube inverters. As far as I am concerned, running an LCD inverter off a PC PSU would be no problem at all.

As for shoving your hands in amongst a heap of live wires, you are just asking for a darwin award. Any sane person knows that you don't mess with live wiring, too much of a risk. The best way to handle the high-voltage from the output side of an inverter is to route it away from the rest of the wiring in your case, not only for safety, but for the potential electrical interference from a High-Voltage AC transmission line messing with your IDE/Power/Ethernet lines, and to cover them with additional insulation like lengths of heatshrink, loom or plastic cable braiding.

Heffo