Quadra 700 Video Ram Problem ...

[franklyn]

I have 2MB of Videoram but the System show up only 512kB of Videoram ...

 

[finkmac]

where did you get those vrams?

try testing them in another machine first.

 

[franklyn]

PurpleRAM 256kB 68-pin VRAM SIMM Macintosh by Jurassic Computing on Tindie

PurpleRAM 256kB 68-pin VRAM SIMM for Apple Macintosh computers

www.tindie.com

I think it worked a few months ago.

I can only test the Simms in a Performa 475 but I think the Simms are ok ...

 

[iigs123]

are you able to set colors > 256? Perhaps tattletech is only reporting _current_ settings, not available or something.

 

[finkmac]

I can only test the Simms in a Performa 475 but I think the Simms are ok ...

test them in that system first

 

[franklyn]

are you able to set colors > 256? Perhaps tattletech is only reporting _current_ settings, not available or something.

I have in the monitor panel under System 7.1 only 640x480 with 256 Color max and with System 7.6.1 640, 832 (256 Color) and 1152 (16 Color) ...

 

[iigs123]

Darn. I have a purple VRAM or two as well, they are quite well made. The only other immediate thing I can think of is to clean the sockets well with deoxit or something.

 

[franklyn]

I'm currently testing the 6 SIMM modules in pairs of 2 in my Performa 475 and one SIMM is defective. The lower half of the screen is faulty. Should I try resoldering the faulty SIMM?

 

[finkmac]

no, you should request a refund from the seller. it would appear they're not doing any product testing after manufacturing.

this isn't the first defective purpleram product i've heard about... buyer beware I guess.

 

[franklyn]

I had no luck. One is faulty. I order a new one ...

 

[finkmac]

why aren't you asking the seller to replace it? you'd risk getting another defective one?

 

[franklyn]

I no longer have the paper/invoice, and reordering would be faster.

I've resoldered the faulty SIMM several times, even using HotAir, and I'm convinced that one of the two RAM chips is defective. These are all old parts, as they haven't been manufactured for over 30 years.

 

[Siliconinsider]

@franklyn, reach out to me, I always exchange defective products. I do test everything before shipping of course, but it's impossible to get it 100% right. Sometime damages happen during shipping. Some of my products are made using original new old stock components like VRAM, they are 30+ years old...

​

 

[franklyn]

Yes it works before fine when I buy it and put it in the Quadra.

I had already soldered it, so it didn't occur to me to send the part in.


I don't always use the computers, and they might be packed away for a year or so.

 

[Siliconinsider]

@franklyn I refunded your second order, your replacement has been sent. Thanks for your trust.

 

[franklyn]

Thank you very much.

I ordered SQJ40 SMD sockets and soldered two of them onto the SIMM so I have a opportunity to test if and which chip is defective.


Question: Can I add another 512k chip to give the Quadra only 1MB of video RAM? And if so, which two of the six sockets do I need to use?