You dont mention if you are using dual sided or single sided chips.
If your machine only has two slots for chips it may not be able to handle two double sided chips. It may do fine with one single sided and one dual sided but give you the problems that you describe with two dual sided chips.
Thong_Ispector
Practically a Master Poster
638 posts since Nov 2004
Reputation Points: 16
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Memory for HP Pavilion 8776c
Standard Memory : 128MB
Maximum Memory : 512MB Memory Banks : 2
Available Memory Sockets : 2
HPPC000064MP1536A 64M PC-133 module for HP No. P1536A memory
$ 27
HPPC000128MP1537A 128M PC-133 DIMM for HP No. P1537A memory
$ 31
HPPC000256MP1538A 256M PC-133 DIMM for HP No. P1538A memory
$ 56
Thong_Ispector
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638 posts since Nov 2004
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Sorry, I DO NOT mean to imply I am selling anything. I just did a cut and paste from a site to show your system should be able to go to 512 meg...
Even though some people use the word DIMM they dont always mean to say Dual Inline Memory Module... Sometimes they really mean Single...
Thong_Ispector
Practically a Master Poster
638 posts since Nov 2004
Reputation Points: 16
Solved Threads: 19
At this point I would suggest you try HP Ram modules...
Did your supplier guarantee compatibility...
Everything says the box will handle 512meg... That is a non-issue...
Thong_Ispector
Practically a Master Poster
638 posts since Nov 2004
Reputation Points: 16
Solved Threads: 19